sys/netinet6/ip6_output.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the project nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $
  32  */
  33
  34 /*-
  35  * Copyright (c) 1982, 1986, 1988, 1990, 1993
  36  *      The Regents of the University of California.  All rights reserved.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 3. Neither the name of the University nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  60  * SUCH DAMAGE.
  61  *
  62  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  63  */
  64
  65 #include <sys/cdefs.h>
  66 #include "opt_inet.h"
  67 #include "opt_inet6.h"
  68 #include "opt_ipsec.h"
  69 #include "opt_kern_tls.h"
  70 #include "opt_ratelimit.h"
  71 #include "opt_route.h"
  72 #include "opt_rss.h"
  73 #include "opt_sctp.h"
  74
  75 #include <sys/param.h>
  76 #include <sys/kernel.h>
  77 #include <sys/ktls.h>
  78 #include <sys/malloc.h>
  79 #include <sys/mbuf.h>
  80 #include <sys/errno.h>
  81 #include <sys/priv.h>
  82 #include <sys/proc.h>
  83 #include <sys/protosw.h>
  84 #include <sys/socket.h>
  85 #include <sys/socketvar.h>
  86 #include <sys/syslog.h>
  87 #include <sys/ucred.h>
  88
  89 #include <machine/in_cksum.h>
  90
  91 #include <net/if.h>
  92 #include <net/if_var.h>
  93 #include <net/if_private.h>
  94 #include <net/if_vlan_var.h>
  95 #include <net/if_llatbl.h>
  96 #include <net/ethernet.h>
  97 #include <net/netisr.h>
  98 #include <net/route.h>
  99 #include <net/route/nhop.h>
 100 #include <net/pfil.h>
 101 #include <net/rss_config.h>
 102 #include <net/vnet.h>
 103
 104 #include <netinet/in.h>
 105 #include <netinet/in_var.h>
 106 #include <netinet/ip_var.h>
 107 #include <netinet6/in6_fib.h>
 108 #include <netinet6/in6_var.h>
 109 #include <netinet/ip6.h>
 110 #include <netinet/icmp6.h>
 111 #include <netinet6/ip6_var.h>
 112 #include <netinet/in_pcb.h>
 113 #include <netinet/tcp_var.h>
 114 #include <netinet6/nd6.h>
 115 #include <netinet6/in6_rss.h>
 116
 117 #include <netipsec/ipsec_support.h>
 118 #if defined(SCTP) || defined(SCTP_SUPPORT)
 119 #include <netinet/sctp.h>
 120 #include <netinet/sctp_crc32.h>
 121 #endif
 122
 123 #include <netinet6/scope6_var.h>
 124
 125 extern int in6_mcast_loop;
 126
 127 struct ip6_exthdrs {
 128         struct mbuf *ip6e_ip6;
 129         struct mbuf *ip6e_hbh;
 130         struct mbuf *ip6e_dest1;
 131         struct mbuf *ip6e_rthdr;
 132         struct mbuf *ip6e_dest2;
 133 };
 134
 135 static MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
 136
 137 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
 138                            struct ucred *, int);
 139 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
 140         struct socket *, struct sockopt *);
 141 static int ip6_getpcbopt(struct inpcb *, int, struct sockopt *);
 142 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
 143         struct ucred *, int, int, int);
 144
 145 static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
 146 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
 147         struct ip6_frag **);
 148 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
 149 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
 150 static int ip6_getpmtu(struct route_in6 *, int,
 151         struct ifnet *, const struct in6_addr *, u_long *, int *, u_int,
 152         u_int);
 153 static int ip6_calcmtu(struct ifnet *, const struct in6_addr *, u_long,
 154         u_long *, int *, u_int);
 155 static int ip6_getpmtu_ctl(u_int, const struct in6_addr *, u_long *);
 156 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
 157
 158 /*
 159  * Make an extension header from option data.  hp is the source,
 160  * mp is the destination, and _ol is the optlen.
 161  */
 162 #define MAKE_EXTHDR(hp, mp, _ol)                                        \
 163     do {                                                                \
 164         if (hp) {                                                       \
 165                 struct ip6_ext *eh = (struct ip6_ext *)(hp);            \
 166                 error = ip6_copyexthdr((mp), (caddr_t)(hp),             \
 167                     ((eh)->ip6e_len + 1) << 3);                         \
 168                 if (error)                                              \
 169                         goto freehdrs;                                  \
 170                 (_ol) += (*(mp))->m_len;                                \
 171         }                                                               \
 172     } while (/*CONSTCOND*/ 0)
 173
 174 /*
 175  * Form a chain of extension headers.
 176  * m is the extension header mbuf
 177  * mp is the previous mbuf in the chain
 178  * p is the next header
 179  * i is the type of option.
 180  */
 181 #define MAKE_CHAIN(m, mp, p, i)\
 182     do {\
 183         if (m) {\
 184                 if (!hdrsplit) \
 185                         panic("%s:%d: assumption failed: "\
 186                             "hdr not split: hdrsplit %d exthdrs %p",\
 187                             __func__, __LINE__, hdrsplit, &exthdrs);\
 188                 *mtod((m), u_char *) = *(p);\
 189                 *(p) = (i);\
 190                 p = mtod((m), u_char *);\
 191                 (m)->m_next = (mp)->m_next;\
 192                 (mp)->m_next = (m);\
 193                 (mp) = (m);\
 194         }\
 195     } while (/*CONSTCOND*/ 0)
 196
 197 void
 198 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
 199 {
 200         u_short csum;
 201
 202         csum = in_cksum_skip(m, offset + plen, offset);
 203         if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
 204                 csum = 0xffff;
 205         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 206
 207         if (offset + sizeof(csum) > m->m_len)
 208                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
 209         else
 210                 *(u_short *)mtodo(m, offset) = csum;
 211 }
 212
 213 static void
 214 ip6_output_delayed_csum(struct mbuf *m, struct ifnet *ifp, int csum_flags,
 215     int plen, int optlen)
 216 {
 217
 218         KASSERT((plen >= optlen), ("%s:%d: plen %d < optlen %d, m %p, ifp %p "
 219             "csum_flags %#x",
 220             __func__, __LINE__, plen, optlen, m, ifp, csum_flags));
 221
 222         if (csum_flags & CSUM_DELAY_DATA_IPV6) {
 223                 in6_delayed_cksum(m, plen - optlen,
 224                     sizeof(struct ip6_hdr) + optlen);
 225                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
 226         }
 227 #if defined(SCTP) || defined(SCTP_SUPPORT)
 228         if (csum_flags & CSUM_SCTP_IPV6) {
 229                 sctp_delayed_cksum(m, sizeof(struct ip6_hdr) + optlen);
 230                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
 231         }
 232 #endif
 233 }
 234
 235 int
 236 ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
 237     int fraglen , uint32_t id)
 238 {
 239         struct mbuf *m, **mnext, *m_frgpart;
 240         struct ip6_hdr *ip6, *mhip6;
 241         struct ip6_frag *ip6f;
 242         int off;
 243         int error;
 244         int tlen = m0->m_pkthdr.len;
 245
 246         KASSERT((fraglen % 8 == 0), ("Fragment length must be a multiple of 8"));
 247
 248         m = m0;
 249         ip6 = mtod(m, struct ip6_hdr *);
 250         mnext = &m->m_nextpkt;
 251
 252         for (off = hlen; off < tlen; off += fraglen) {
 253                 m = m_gethdr(M_NOWAIT, MT_DATA);
 254                 if (!m) {
 255                         IP6STAT_INC(ip6s_odropped);
 256                         return (ENOBUFS);
 257                 }
 258
 259                 /*
 260                  * Make sure the complete packet header gets copied
 261                  * from the originating mbuf to the newly created
 262                  * mbuf. This also ensures that existing firewall
 263                  * classification(s), VLAN tags and so on get copied
 264                  * to the resulting fragmented packet(s):
 265                  */
 266                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 267                         m_free(m);
 268                         IP6STAT_INC(ip6s_odropped);
 269                         return (ENOBUFS);
 270                 }
 271
 272                 *mnext = m;
 273                 mnext = &m->m_nextpkt;
 274                 m->m_data += max_linkhdr;
 275                 mhip6 = mtod(m, struct ip6_hdr *);
 276                 *mhip6 = *ip6;
 277                 m->m_len = sizeof(*mhip6);
 278                 error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
 279                 if (error) {
 280                         IP6STAT_INC(ip6s_odropped);
 281                         return (error);
 282                 }
 283                 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
 284                 if (off + fraglen >= tlen)
 285                         fraglen = tlen - off;
 286                 else
 287                         ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
 288                 mhip6->ip6_plen = htons((u_short)(fraglen + hlen +
 289                     sizeof(*ip6f) - sizeof(struct ip6_hdr)));
 290                 if ((m_frgpart = m_copym(m0, off, fraglen, M_NOWAIT)) == NULL) {
 291                         IP6STAT_INC(ip6s_odropped);
 292                         return (ENOBUFS);
 293                 }
 294                 m_cat(m, m_frgpart);
 295                 m->m_pkthdr.len = fraglen + hlen + sizeof(*ip6f);
 296                 ip6f->ip6f_reserved = 0;
 297                 ip6f->ip6f_ident = id;
 298                 ip6f->ip6f_nxt = nextproto;
 299                 IP6STAT_INC(ip6s_ofragments);
 300                 in6_ifstat_inc(ifp, ifs6_out_fragcreat);
 301         }
 302
 303         return (0);
 304 }
 305
 306 static int
 307 ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp,
 308     struct mbuf *m, struct sockaddr_in6 *dst, struct route_in6 *ro,
 309     bool stamp_tag)
 310 {
 311 #ifdef KERN_TLS
 312         struct ktls_session *tls = NULL;
 313 #endif
 314         struct m_snd_tag *mst;
 315         int error;
 316
 317         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 318         mst = NULL;
 319
 320 #ifdef KERN_TLS
 321         /*
 322          * If this is an unencrypted TLS record, save a reference to
 323          * the record.  This local reference is used to call
 324          * ktls_output_eagain after the mbuf has been freed (thus
 325          * dropping the mbuf's reference) in if_output.
 326          */
 327         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 328                 tls = ktls_hold(m->m_next->m_epg_tls);
 329                 mst = tls->snd_tag;
 330
 331                 /*
 332                  * If a TLS session doesn't have a valid tag, it must
 333                  * have had an earlier ifp mismatch, so drop this
 334                  * packet.
 335                  */
 336                 if (mst == NULL) {
 337                         m_freem(m);
 338                         error = EAGAIN;
 339                         goto done;
 340                 }
 341                 /*
 342                  * Always stamp tags that include NIC ktls.
 343                  */
 344                 stamp_tag = true;
 345         }
 346 #endif
 347 #ifdef RATELIMIT
 348         if (inp != NULL && mst == NULL) {
 349                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 350                     (inp->inp_snd_tag != NULL &&
 351                     inp->inp_snd_tag->ifp != ifp))
 352                         in_pcboutput_txrtlmt(inp, ifp, m);
 353
 354                 if (inp->inp_snd_tag != NULL)
 355                         mst = inp->inp_snd_tag;
 356         }
 357 #endif
 358         if (stamp_tag && mst != NULL) {
 359                 KASSERT(m->m_pkthdr.rcvif == NULL,
 360                     ("trying to add a send tag to a forwarded packet"));
 361                 if (mst->ifp != ifp) {
 362                         m_freem(m);
 363                         error = EAGAIN;
 364                         goto done;
 365                 }
 366
 367                 /* stamp send tag on mbuf */
 368                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 369                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 370         }
 371
 372         error = nd6_output_ifp(ifp, origifp, m, dst, (struct route *)ro);
 373
 374 done:
 375         /* Check for route change invalidating send tags. */
 376 #ifdef KERN_TLS
 377         if (tls != NULL) {
 378                 if (error == EAGAIN)
 379                         error = ktls_output_eagain(inp, tls);
 380                 ktls_free(tls);
 381         }
 382 #endif
 383 #ifdef RATELIMIT
 384         if (error == EAGAIN)
 385                 in_pcboutput_eagain(inp);
 386 #endif
 387         return (error);
 388 }
 389
 390 /*
 391  * IP6 output.
 392  * The packet in mbuf chain m contains a skeletal IP6 header (with pri, len,
 393  * nxt, hlim, src, dst).
 394  * This function may modify ver and hlim only.
 395  * The mbuf chain containing the packet will be freed.
 396  * The mbuf opt, if present, will not be freed.
 397  * If route_in6 ro is present and has ro_nh initialized, route lookup would be
 398  * skipped and ro->ro_nh would be used. If ro is present but ro->ro_nh is NULL,
 399  * then result of route lookup is stored in ro->ro_nh.
 400  *
 401  * Type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and nd_ifinfo.linkmtu
 402  * is uint32_t.  So we use u_long to hold largest one, which is rt_mtu.
 403  *
 404  * ifpp - XXX: just for statistics
 405  */
 406 int
 407 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
 408     struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
 409     struct ifnet **ifpp, struct inpcb *inp)
 410 {
 411         struct ip6_hdr *ip6;
 412         struct ifnet *ifp, *origifp;
 413         struct mbuf *m = m0;
 414         struct mbuf *mprev;
 415         struct route_in6 *ro_pmtu;
 416         struct nhop_object *nh;
 417         struct sockaddr_in6 *dst, sin6, src_sa, dst_sa;
 418         struct in6_addr odst;
 419         u_char *nexthdrp;
 420         int tlen, len;
 421         int error = 0;
 422         int vlan_pcp = -1;
 423         struct in6_ifaddr *ia = NULL;
 424         u_long mtu;
 425         int alwaysfrag, dontfrag;
 426         u_int32_t optlen, plen = 0, unfragpartlen;
 427         struct ip6_exthdrs exthdrs;
 428         struct in6_addr src0, dst0;
 429         u_int32_t zone;
 430         bool hdrsplit;
 431         int sw_csum, tso;
 432         int needfiblookup;
 433         uint32_t fibnum;
 434         struct m_tag *fwd_tag = NULL;
 435         uint32_t id;
 436
 437         NET_EPOCH_ASSERT();
 438
 439         if (inp != NULL) {
 440                 INP_LOCK_ASSERT(inp);
 441                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 442                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 443                         /* Unconditionally set flowid. */
 444                         m->m_pkthdr.flowid = inp->inp_flowid;
 445                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 446                 }
 447                 if ((inp->inp_flags2 & INP_2PCP_SET) != 0)
 448                         vlan_pcp = (inp->inp_flags2 & INP_2PCP_MASK) >>
 449                             INP_2PCP_SHIFT;
 450 #ifdef NUMA
 451                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 452 #endif
 453         }
 454
 455 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 456         /*
 457          * IPSec checking which handles several cases.
 458          * FAST IPSEC: We re-injected the packet.
 459          * XXX: need scope argument.
 460          */
 461         if (IPSEC_ENABLED(ipv6)) {
 462                 m = mb_unmapped_to_ext(m);
 463                 if (m == NULL) {
 464                         IP6STAT_INC(ip6s_odropped);
 465                         error = ENOBUFS;
 466                         goto bad;
 467                 }
 468                 if ((error = IPSEC_OUTPUT(ipv6, m, inp)) != 0) {
 469                         if (error == EINPROGRESS)
 470                                 error = 0;
 471                         goto done;
 472                 }
 473         }
 474 #endif /* IPSEC */
 475
 476         /* Source address validation. */
 477         ip6 = mtod(m, struct ip6_hdr *);
 478         if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
 479             (flags & IPV6_UNSPECSRC) == 0) {
 480                 error = EOPNOTSUPP;
 481                 IP6STAT_INC(ip6s_badscope);
 482                 goto bad;
 483         }
 484         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
 485                 error = EOPNOTSUPP;
 486                 IP6STAT_INC(ip6s_badscope);
 487                 goto bad;
 488         }
 489
 490         /*
 491          * If we are given packet options to add extension headers prepare them.
 492          * Calculate the total length of the extension header chain.
 493          * Keep the length of the unfragmentable part for fragmentation.
 494          */
 495         bzero(&exthdrs, sizeof(exthdrs));
 496         optlen = 0;
 497         unfragpartlen = sizeof(struct ip6_hdr);
 498         if (opt) {
 499                 /* Hop-by-Hop options header. */
 500                 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh, optlen);
 501
 502                 /* Destination options header (1st part). */
 503                 if (opt->ip6po_rthdr) {
 504 #ifndef RTHDR_SUPPORT_IMPLEMENTED
 505                         /*
 506                          * If there is a routing header, discard the packet
 507                          * right away here. RH0/1 are obsolete and we do not
 508                          * currently support RH2/3/4.
 509                          * People trying to use RH253/254 may want to disable
 510                          * this check.
 511                          * The moment we do support any routing header (again)
 512                          * this block should check the routing type more
 513                          * selectively.
 514                          */
 515                         error = EINVAL;
 516                         goto bad;
 517 #endif
 518
 519                         /*
 520                          * Destination options header (1st part).
 521                          * This only makes sense with a routing header.
 522                          * See Section 9.2 of RFC 3542.
 523                          * Disabling this part just for MIP6 convenience is
 524                          * a bad idea.  We need to think carefully about a
 525                          * way to make the advanced API coexist with MIP6
 526                          * options, which might automatically be inserted in
 527                          * the kernel.
 528                          */
 529                         MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1,
 530                             optlen);
 531                 }
 532                 /* Routing header. */
 533                 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr, optlen);
 534
 535                 unfragpartlen += optlen;
 536
 537                 /*
 538                  * NOTE: we don't add AH/ESP length here (done in
 539                  * ip6_ipsec_output()).
 540                  */
 541
 542                 /* Destination options header (2nd part). */
 543                 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2, optlen);
 544         }
 545
 546         /*
 547          * If there is at least one extension header,
 548          * separate IP6 header from the payload.
 549          */
 550         hdrsplit = false;
 551         if (optlen) {
 552                 if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 553                         m = NULL;
 554                         goto freehdrs;
 555                 }
 556                 m = exthdrs.ip6e_ip6;
 557                 ip6 = mtod(m, struct ip6_hdr *);
 558                 hdrsplit = true;
 559         }
 560
 561         /* Adjust mbuf packet header length. */
 562         m->m_pkthdr.len += optlen;
 563         plen = m->m_pkthdr.len - sizeof(*ip6);
 564
 565         /* If this is a jumbo payload, insert a jumbo payload option. */
 566         if (plen > IPV6_MAXPACKET) {
 567                 if (!hdrsplit) {
 568                         if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
 569                                 m = NULL;
 570                                 goto freehdrs;
 571                         }
 572                         m = exthdrs.ip6e_ip6;
 573                         ip6 = mtod(m, struct ip6_hdr *);
 574                         hdrsplit = true;
 575                 }
 576                 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
 577                         goto freehdrs;
 578                 ip6->ip6_plen = 0;
 579         } else
 580                 ip6->ip6_plen = htons(plen);
 581         nexthdrp = &ip6->ip6_nxt;
 582
 583         if (optlen) {
 584                 /*
 585                  * Concatenate headers and fill in next header fields.
 586                  * Here we have, on "m"
 587                  *      IPv6 payload
 588                  * and we insert headers accordingly.
 589                  * Finally, we should be getting:
 590                  *      IPv6 hbh dest1 rthdr ah* [esp* dest2 payload].
 591                  *
 592                  * During the header composing process "m" points to IPv6
 593                  * header.  "mprev" points to an extension header prior to esp.
 594                  */
 595                 mprev = m;
 596
 597                 /*
 598                  * We treat dest2 specially.  This makes IPsec processing
 599                  * much easier.  The goal here is to make mprev point the
 600                  * mbuf prior to dest2.
 601                  *
 602                  * Result: IPv6 dest2 payload.
 603                  * m and mprev will point to IPv6 header.
 604                  */
 605                 if (exthdrs.ip6e_dest2) {
 606                         if (!hdrsplit)
 607                                 panic("%s:%d: assumption failed: "
 608                                     "hdr not split: hdrsplit %d exthdrs %p",
 609                                     __func__, __LINE__, hdrsplit, &exthdrs);
 610                         exthdrs.ip6e_dest2->m_next = m->m_next;
 611                         m->m_next = exthdrs.ip6e_dest2;
 612                         *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
 613                         ip6->ip6_nxt = IPPROTO_DSTOPTS;
 614                 }
 615
 616                 /*
 617                  * Result: IPv6 hbh dest1 rthdr dest2 payload.
 618                  * m will point to IPv6 header.  mprev will point to the
 619                  * extension header prior to dest2 (rthdr in the above case).
 620                  */
 621                 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
 622                 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
 623                            IPPROTO_DSTOPTS);
 624                 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
 625                            IPPROTO_ROUTING);
 626         }
 627
 628         IP6STAT_INC(ip6s_localout);
 629
 630         /* Route packet. */
 631         ro_pmtu = ro;
 632         if (opt && opt->ip6po_rthdr)
 633                 ro = &opt->ip6po_route;
 634         if (ro != NULL)
 635                 dst = (struct sockaddr_in6 *)&ro->ro_dst;
 636         else
 637                 dst = &sin6;
 638         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 639
 640 again:
 641         /*
 642          * If specified, try to fill in the traffic class field.
 643          * Do not override if a non-zero value is already set.
 644          * We check the diffserv field and the ECN field separately.
 645          */
 646         if (opt && opt->ip6po_tclass >= 0) {
 647                 int mask = 0;
 648
 649                 if (IPV6_DSCP(ip6) == 0)
 650                         mask |= 0xfc;
 651                 if (IPV6_ECN(ip6) == 0)
 652                         mask |= 0x03;
 653                 if (mask != 0)
 654                         ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20);
 655         }
 656
 657         /* Fill in or override the hop limit field, if necessary. */
 658         if (opt && opt->ip6po_hlim != -1)
 659                 ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
 660         else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 661                 if (im6o != NULL)
 662                         ip6->ip6_hlim = im6o->im6o_multicast_hlim;
 663                 else
 664                         ip6->ip6_hlim = V_ip6_defmcasthlim;
 665         }
 666
 667         if (ro == NULL || ro->ro_nh == NULL) {
 668                 bzero(dst, sizeof(*dst));
 669                 dst->sin6_family = AF_INET6;
 670                 dst->sin6_len = sizeof(*dst);
 671                 dst->sin6_addr = ip6->ip6_dst;
 672         }
 673         /*
 674          * Validate route against routing table changes.
 675          * Make sure that the address family is set in route.
 676          */
 677         nh = NULL;
 678         ifp = NULL;
 679         mtu = 0;
 680         if (ro != NULL) {
 681                 if (ro->ro_nh != NULL && inp != NULL) {
 682                         ro->ro_dst.sin6_family = AF_INET6; /* XXX KASSERT? */
 683                         NH_VALIDATE((struct route *)ro, &inp->inp_rt_cookie,
 684                             fibnum);
 685                 }
 686                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 687                     (!NH_IS_VALID(ro->ro_nh) ||
 688                     ro->ro_dst.sin6_family != AF_INET6 ||
 689                     !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)))
 690                         RO_INVALIDATE_CACHE(ro);
 691
 692                 if (ro->ro_nh != NULL && fwd_tag == NULL &&
 693                     ro->ro_dst.sin6_family == AF_INET6 &&
 694                     IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, &ip6->ip6_dst)) {
 695                         /* Nexthop is valid and contains valid ifp */
 696                         nh = ro->ro_nh;
 697                 } else {
 698                         if (ro->ro_lle)
 699                                 LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 700                         ro->ro_lle = NULL;
 701                         if (fwd_tag == NULL) {
 702                                 bzero(&dst_sa, sizeof(dst_sa));
 703                                 dst_sa.sin6_family = AF_INET6;
 704                                 dst_sa.sin6_len = sizeof(dst_sa);
 705                                 dst_sa.sin6_addr = ip6->ip6_dst;
 706                         }
 707                         error = in6_selectroute(&dst_sa, opt, im6o, ro, &ifp,
 708                             &nh, fibnum, m->m_pkthdr.flowid);
 709                         if (error != 0) {
 710                                 IP6STAT_INC(ip6s_noroute);
 711                                 if (ifp != NULL)
 712                                         in6_ifstat_inc(ifp, ifs6_out_discard);
 713                                 goto bad;
 714                         }
 715                         /*
 716                          * At this point at least @ifp is not NULL
 717                          * Can be the case when dst is multicast, link-local or
 718                          * interface is explicitly specificed by the caller.
 719                          */
 720                 }
 721                 if (nh == NULL) {
 722                         /*
 723                          * If in6_selectroute() does not return a nexthop
 724                          * dst may not have been updated.
 725                          */
 726                         *dst = dst_sa;  /* XXX */
 727                         origifp = ifp;
 728                         mtu = ifp->if_mtu;
 729                 } else {
 730                         ifp = nh->nh_ifp;
 731                         origifp = nh->nh_aifp;
 732                         ia = (struct in6_ifaddr *)(nh->nh_ifa);
 733                         counter_u64_add(nh->nh_pksent, 1);
 734                 }
 735         } else {
 736                 struct nhop_object *nh;
 737                 struct in6_addr kdst;
 738                 uint32_t scopeid;
 739
 740                 if (fwd_tag == NULL) {
 741                         bzero(&dst_sa, sizeof(dst_sa));
 742                         dst_sa.sin6_family = AF_INET6;
 743                         dst_sa.sin6_len = sizeof(dst_sa);
 744                         dst_sa.sin6_addr = ip6->ip6_dst;
 745                 }
 746
 747                 if (IN6_IS_ADDR_MULTICAST(&dst_sa.sin6_addr) &&
 748                     im6o != NULL &&
 749                     (ifp = im6o->im6o_multicast_ifp) != NULL) {
 750                         /* We do not need a route lookup. */
 751                         *dst = dst_sa;  /* XXX */
 752                         origifp = ifp;
 753                         goto nonh6lookup;
 754                 }
 755
 756                 in6_splitscope(&dst_sa.sin6_addr, &kdst, &scopeid);
 757
 758                 if (IN6_IS_ADDR_MC_LINKLOCAL(&dst_sa.sin6_addr) ||
 759                     IN6_IS_ADDR_MC_NODELOCAL(&dst_sa.sin6_addr)) {
 760                         if (scopeid > 0) {
 761                                 ifp = in6_getlinkifnet(scopeid);
 762                                 if (ifp == NULL) {
 763                                         error = EHOSTUNREACH;
 764                                         goto bad;
 765                                 }
 766                                 *dst = dst_sa;  /* XXX */
 767                                 origifp = ifp;
 768                                 goto nonh6lookup;
 769                         }
 770                 }
 771
 772                 nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE,
 773                     m->m_pkthdr.flowid);
 774                 if (nh == NULL) {
 775                         IP6STAT_INC(ip6s_noroute);
 776                         /* No ifp in6_ifstat_inc(ifp, ifs6_out_discard); */
 777                         error = EHOSTUNREACH;
 778                         goto bad;
 779                 }
 780
 781                 ifp = nh->nh_ifp;
 782                 origifp = nh->nh_aifp;
 783                 ia = ifatoia6(nh->nh_ifa);
 784                 if (nh->nh_flags & NHF_GATEWAY)
 785                         dst->sin6_addr = nh->gw6_sa.sin6_addr;
 786                 else if (fwd_tag != NULL)
 787                         dst->sin6_addr = dst_sa.sin6_addr;
 788 nonh6lookup:
 789                 ;
 790         }
 791         /*
 792          * At this point ifp MUST be pointing to the valid transmit ifp.
 793          * origifp MUST be valid and pointing to either the same ifp or,
 794          * in case of loopback output, to the interface which ip6_src
 795          * belongs to.
 796          * Examples:
 797          *  fe80::1%em0 -> fe80::2%em0 -> ifp=em0, origifp=em0
 798          *  fe80::1%em0 -> fe80::1%em0 -> ifp=lo0, origifp=em0
 799          *  ::1 -> ::1 -> ifp=lo0, origifp=lo0
 800          *
 801          * mtu can be 0 and will be refined later.
 802          */
 803         KASSERT((ifp != NULL), ("output interface must not be NULL"));
 804         KASSERT((origifp != NULL), ("output address interface must not be NULL"));
 805
 806         if ((flags & IPV6_FORWARDING) == 0) {
 807                 /* XXX: the FORWARDING flag can be set for mrouting. */
 808                 in6_ifstat_inc(ifp, ifs6_out_request);
 809         }
 810
 811         /* Setup data structures for scope ID checks. */
 812         src0 = ip6->ip6_src;
 813         bzero(&src_sa, sizeof(src_sa));
 814         src_sa.sin6_family = AF_INET6;
 815         src_sa.sin6_len = sizeof(src_sa);
 816         src_sa.sin6_addr = ip6->ip6_src;
 817
 818         dst0 = ip6->ip6_dst;
 819         /* Re-initialize to be sure. */
 820         bzero(&dst_sa, sizeof(dst_sa));
 821         dst_sa.sin6_family = AF_INET6;
 822         dst_sa.sin6_len = sizeof(dst_sa);
 823         dst_sa.sin6_addr = ip6->ip6_dst;
 824
 825         /* Check for valid scope ID. */
 826         if (in6_setscope(&src0, origifp, &zone) == 0 &&
 827             sa6_recoverscope(&src_sa) == 0 && zone == src_sa.sin6_scope_id &&
 828             in6_setscope(&dst0, origifp, &zone) == 0 &&
 829             sa6_recoverscope(&dst_sa) == 0 && zone == dst_sa.sin6_scope_id) {
 830                 /*
 831                  * The outgoing interface is in the zone of the source
 832                  * and destination addresses.
 833                  *
 834                  */
 835         } else if ((origifp->if_flags & IFF_LOOPBACK) == 0 ||
 836             sa6_recoverscope(&src_sa) != 0 ||
 837             sa6_recoverscope(&dst_sa) != 0 ||
 838             dst_sa.sin6_scope_id == 0 ||
 839             (src_sa.sin6_scope_id != 0 &&
 840             src_sa.sin6_scope_id != dst_sa.sin6_scope_id) ||
 841             ifnet_byindex(dst_sa.sin6_scope_id) == NULL) {
 842                 /*
 843                  * If the destination network interface is not a
 844                  * loopback interface, or the destination network
 845                  * address has no scope ID, or the source address has
 846                  * a scope ID set which is different from the
 847                  * destination address one, or there is no network
 848                  * interface representing this scope ID, the address
 849                  * pair is considered invalid.
 850                  */
 851                 IP6STAT_INC(ip6s_badscope);
 852                 in6_ifstat_inc(origifp, ifs6_out_discard);
 853                 if (error == 0)
 854                         error = EHOSTUNREACH; /* XXX */
 855                 goto bad;
 856         }
 857         /* All scope ID checks are successful. */
 858
 859         if (nh && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 860                 if (opt && opt->ip6po_nextroute.ro_nh) {
 861                         /*
 862                          * The nexthop is explicitly specified by the
 863                          * application.  We assume the next hop is an IPv6
 864                          * address.
 865                          */
 866                         dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
 867                 }
 868                 else if ((nh->nh_flags & NHF_GATEWAY))
 869                         dst = &nh->gw6_sa;
 870         }
 871
 872         if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 873                 m->m_flags &= ~(M_BCAST | M_MCAST); /* Just in case. */
 874         } else {
 875                 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
 876                 in6_ifstat_inc(ifp, ifs6_out_mcast);
 877
 878                 /* Confirm that the outgoing interface supports multicast. */
 879                 if (!(ifp->if_flags & IFF_MULTICAST)) {
 880                         IP6STAT_INC(ip6s_noroute);
 881                         in6_ifstat_inc(ifp, ifs6_out_discard);
 882                         error = ENETUNREACH;
 883                         goto bad;
 884                 }
 885                 if ((im6o == NULL && in6_mcast_loop) ||
 886                     (im6o && im6o->im6o_multicast_loop)) {
 887                         /*
 888                          * Loop back multicast datagram if not expressly
 889                          * forbidden to do so, even if we have not joined
 890                          * the address; protocols will filter it later,
 891                          * thus deferring a hash lookup and lock acquisition
 892                          * at the expense of an m_copym().
 893                          */
 894                         ip6_mloopback(ifp, m);
 895                 } else {
 896                         /*
 897                          * If we are acting as a multicast router, perform
 898                          * multicast forwarding as if the packet had just
 899                          * arrived on the interface to which we are about
 900                          * to send.  The multicast forwarding function
 901                          * recursively calls this function, using the
 902                          * IPV6_FORWARDING flag to prevent infinite recursion.
 903                          *
 904                          * Multicasts that are looped back by ip6_mloopback(),
 905                          * above, will be forwarded by the ip6_input() routine,
 906                          * if necessary.
 907                          */
 908                         if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
 909                                 /*
 910                                  * XXX: ip6_mforward expects that rcvif is NULL
 911                                  * when it is called from the originating path.
 912                                  * However, it may not always be the case.
 913                                  */
 914                                 m->m_pkthdr.rcvif = NULL;
 915                                 if (ip6_mforward(ip6, ifp, m) != 0) {
 916                                         m_freem(m);
 917                                         goto done;
 918                                 }
 919                         }
 920                 }
 921                 /*
 922                  * Multicasts with a hoplimit of zero may be looped back,
 923                  * above, but must not be transmitted on a network.
 924                  * Also, multicasts addressed to the loopback interface
 925                  * are not sent -- the above call to ip6_mloopback() will
 926                  * loop back a copy if this host actually belongs to the
 927                  * destination group on the loopback interface.
 928                  */
 929                 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
 930                     IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
 931                         m_freem(m);
 932                         goto done;
 933                 }
 934         }
 935
 936         /*
 937          * Fill the outgoing inteface to tell the upper layer
 938          * to increment per-interface statistics.
 939          */
 940         if (ifpp)
 941                 *ifpp = ifp;
 942
 943         /* Determine path MTU. */
 944         if ((error = ip6_getpmtu(ro_pmtu, ro != ro_pmtu, ifp, &ip6->ip6_dst,
 945                     &mtu, &alwaysfrag, fibnum, *nexthdrp)) != 0)
 946                 goto bad;
 947         KASSERT(mtu > 0, ("%s:%d: mtu %ld, ro_pmtu %p ro %p ifp %p "
 948             "alwaysfrag %d fibnum %u\n", __func__, __LINE__, mtu, ro_pmtu, ro,
 949             ifp, alwaysfrag, fibnum));
 950
 951         /*
 952          * The caller of this function may specify to use the minimum MTU
 953          * in some cases.
 954          * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
 955          * setting.  The logic is a bit complicated; by default, unicast
 956          * packets will follow path MTU while multicast packets will be sent at
 957          * the minimum MTU.  If IP6PO_MINMTU_ALL is specified, all packets
 958          * including unicast ones will be sent at the minimum MTU.  Multicast
 959          * packets will always be sent at the minimum MTU unless
 960          * IP6PO_MINMTU_DISABLE is explicitly specified.
 961          * See RFC 3542 for more details.
 962          */
 963         if (mtu > IPV6_MMTU) {
 964                 if ((flags & IPV6_MINMTU))
 965                         mtu = IPV6_MMTU;
 966                 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
 967                         mtu = IPV6_MMTU;
 968                 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 969                          (opt == NULL ||
 970                           opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
 971                         mtu = IPV6_MMTU;
 972                 }
 973         }
 974
 975         /*
 976          * Clear embedded scope identifiers if necessary.
 977          * in6_clearscope() will touch the addresses only when necessary.
 978          */
 979         in6_clearscope(&ip6->ip6_src);
 980         in6_clearscope(&ip6->ip6_dst);
 981
 982         /*
 983          * If the outgoing packet contains a hop-by-hop options header,
 984          * it must be examined and processed even by the source node.
 985          * (RFC 2460, section 4.)
 986          */
 987         if (exthdrs.ip6e_hbh) {
 988                 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
 989                 u_int32_t dummy; /* XXX unused */
 990                 u_int32_t plen = 0; /* XXX: ip6_process will check the value */
 991
 992 #ifdef DIAGNOSTIC
 993                 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
 994                         panic("ip6e_hbh is not contiguous");
 995 #endif
 996                 /*
 997                  *  XXX: if we have to send an ICMPv6 error to the sender,
 998                  *       we need the M_LOOP flag since icmp6_error() expects
 999                  *       the IPv6 and the hop-by-hop options header are
1000                  *       contiguous unless the flag is set.
1001                  */
1002                 m->m_flags |= M_LOOP;
1003                 m->m_pkthdr.rcvif = ifp;
1004                 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
1005                     ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
1006                     &dummy, &plen) < 0) {
1007                         /* m was already freed at this point. */
1008                         error = EINVAL;/* better error? */
1009                         goto done;
1010                 }
1011                 m->m_flags &= ~M_LOOP; /* XXX */
1012                 m->m_pkthdr.rcvif = NULL;
1013         }
1014
1015         /* Jump over all PFIL processing if hooks are not active. */
1016         if (!PFIL_HOOKED_OUT(V_inet6_pfil_head))
1017                 goto passout;
1018
1019         odst = ip6->ip6_dst;
1020         /* Run through list of hooks for output packets. */
1021         switch (pfil_mbuf_out(V_inet6_pfil_head, &m, ifp, inp)) {
1022         case PFIL_PASS:
1023                 ip6 = mtod(m, struct ip6_hdr *);
1024                 break;
1025         case PFIL_DROPPED:
1026                 error = EACCES;
1027                 /* FALLTHROUGH */
1028         case PFIL_CONSUMED:
1029                 goto done;
1030         }
1031
1032         needfiblookup = 0;
1033         /* See if destination IP address was changed by packet filter. */
1034         if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
1035                 m->m_flags |= M_SKIP_FIREWALL;
1036                 /* If destination is now ourself drop to ip6_input(). */
1037                 if (in6_localip(&ip6->ip6_dst)) {
1038                         m->m_flags |= M_FASTFWD_OURS;
1039                         if (m->m_pkthdr.rcvif == NULL)
1040                                 m->m_pkthdr.rcvif = V_loif;
1041                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1042                                 m->m_pkthdr.csum_flags |=
1043                                     CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1044                                 m->m_pkthdr.csum_data = 0xffff;
1045                         }
1046 #if defined(SCTP) || defined(SCTP_SUPPORT)
1047                         if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1048                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1049 #endif
1050                         error = netisr_queue(NETISR_IPV6, m);
1051                         goto done;
1052                 } else {
1053                         if (ro != NULL)
1054                                 RO_INVALIDATE_CACHE(ro);
1055                         needfiblookup = 1; /* Redo the routing table lookup. */
1056                 }
1057         }
1058         /* See if fib was changed by packet filter. */
1059         if (fibnum != M_GETFIB(m)) {
1060                 m->m_flags |= M_SKIP_FIREWALL;
1061                 fibnum = M_GETFIB(m);
1062                 if (ro != NULL)
1063                         RO_INVALIDATE_CACHE(ro);
1064                 needfiblookup = 1;
1065         }
1066         if (needfiblookup)
1067                 goto again;
1068
1069         /* See if local, if yes, send it to netisr. */
1070         if (m->m_flags & M_FASTFWD_OURS) {
1071                 if (m->m_pkthdr.rcvif == NULL)
1072                         m->m_pkthdr.rcvif = V_loif;
1073                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
1074                         m->m_pkthdr.csum_flags |=
1075                             CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
1076                         m->m_pkthdr.csum_data = 0xffff;
1077                 }
1078 #if defined(SCTP) || defined(SCTP_SUPPORT)
1079                 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
1080                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1081 #endif
1082                 error = netisr_queue(NETISR_IPV6, m);
1083                 goto done;
1084         }
1085         /* Or forward to some other address? */
1086         if ((m->m_flags & M_IP6_NEXTHOP) &&
1087             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
1088                 if (ro != NULL)
1089                         dst = (struct sockaddr_in6 *)&ro->ro_dst;
1090                 else
1091                         dst = &sin6;
1092                 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
1093                 m->m_flags |= M_SKIP_FIREWALL;
1094                 m->m_flags &= ~M_IP6_NEXTHOP;
1095                 m_tag_delete(m, fwd_tag);
1096                 goto again;
1097         }
1098
1099 passout:
1100         if (vlan_pcp > -1)
1101                 EVL_APPLY_PRI(m, vlan_pcp);
1102
1103         /* Ensure the packet data is mapped if the interface requires it. */
1104         if ((ifp->if_capenable & IFCAP_MEXTPG) == 0) {
1105                 m = mb_unmapped_to_ext(m);
1106                 if (m == NULL) {
1107                         IP6STAT_INC(ip6s_odropped);
1108                         return (ENOBUFS);
1109                 }
1110         }
1111
1112         /*
1113          * Send the packet to the outgoing interface.
1114          * If necessary, do IPv6 fragmentation before sending.
1115          *
1116          * The logic here is rather complex:
1117          * 1: normal case (dontfrag == 0, alwaysfrag == 0)
1118          * 1-a: send as is if tlen <= path mtu
1119          * 1-b: fragment if tlen > path mtu
1120          *
1121          * 2: if user asks us not to fragment (dontfrag == 1)
1122          * 2-a: send as is if tlen <= interface mtu
1123          * 2-b: error if tlen > interface mtu
1124          *
1125          * 3: if we always need to attach fragment header (alwaysfrag == 1)
1126          *      always fragment
1127          *
1128          * 4: if dontfrag == 1 && alwaysfrag == 1
1129          *      error, as we cannot handle this conflicting request.
1130          */
1131         sw_csum = m->m_pkthdr.csum_flags;
1132         if (!hdrsplit) {
1133                 tso = ((sw_csum & ifp->if_hwassist &
1134                     (CSUM_TSO | CSUM_INNER_TSO)) != 0) ? 1 : 0;
1135                 sw_csum &= ~ifp->if_hwassist;
1136         } else
1137                 tso = 0;
1138         /*
1139          * If we added extension headers, we will not do TSO and calculate the
1140          * checksums ourselves for now.
1141          * XXX-BZ  Need a framework to know when the NIC can handle it, even
1142          * with ext. hdrs.
1143          */
1144         ip6_output_delayed_csum(m, ifp, sw_csum, plen, optlen);
1145         /* XXX-BZ m->m_pkthdr.csum_flags &= ~ifp->if_hwassist; */
1146         tlen = m->m_pkthdr.len;
1147
1148         if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
1149                 dontfrag = 1;
1150         else
1151                 dontfrag = 0;
1152         if (dontfrag && alwaysfrag) {   /* Case 4. */
1153                 /* Conflicting request - can't transmit. */
1154                 error = EMSGSIZE;
1155                 goto bad;
1156         }
1157         if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) {      /* Case 2-b. */
1158                 /*
1159                  * Even if the DONTFRAG option is specified, we cannot send the
1160                  * packet when the data length is larger than the MTU of the
1161                  * outgoing interface.
1162                  * Notify the error by sending IPV6_PATHMTU ancillary data if
1163                  * application wanted to know the MTU value. Also return an
1164                  * error code (this is not described in the API spec).
1165                  */
1166                 if (inp != NULL)
1167                         ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
1168                 error = EMSGSIZE;
1169                 goto bad;
1170         }
1171
1172         /* Transmit packet without fragmentation. */
1173         if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* Cases 1-a and 2-a. */
1174                 struct in6_ifaddr *ia6;
1175
1176                 ip6 = mtod(m, struct ip6_hdr *);
1177                 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
1178                 if (ia6) {
1179                         /* Record statistics for this interface address. */
1180                         counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
1181                         counter_u64_add(ia6->ia_ifa.ifa_obytes,
1182                             m->m_pkthdr.len);
1183                 }
1184                 error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1185                     (flags & IP_NO_SND_TAG_RL) ? false : true);
1186                 goto done;
1187         }
1188
1189         /* Try to fragment the packet.  Cases 1-b and 3. */
1190         if (mtu < IPV6_MMTU) {
1191                 /* Path MTU cannot be less than IPV6_MMTU. */
1192                 error = EMSGSIZE;
1193                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1194                 goto bad;
1195         } else if (ip6->ip6_plen == 0) {
1196                 /* Jumbo payload cannot be fragmented. */
1197                 error = EMSGSIZE;
1198                 in6_ifstat_inc(ifp, ifs6_out_fragfail);
1199                 goto bad;
1200         } else {
1201                 u_char nextproto;
1202
1203                 /*
1204                  * Too large for the destination or interface;
1205                  * fragment if possible.
1206                  * Must be able to put at least 8 bytes per fragment.
1207                  */
1208                 if (mtu > IPV6_MAXPACKET)
1209                         mtu = IPV6_MAXPACKET;
1210
1211                 len = (mtu - unfragpartlen - sizeof(struct ip6_frag)) & ~7;
1212                 if (len < 8) {
1213                         error = EMSGSIZE;
1214                         in6_ifstat_inc(ifp, ifs6_out_fragfail);
1215                         goto bad;
1216                 }
1217
1218                 /*
1219                  * If the interface will not calculate checksums on
1220                  * fragmented packets, then do it here.
1221                  * XXX-BZ handle the hw offloading case.  Need flags.
1222                  */
1223                 ip6_output_delayed_csum(m, ifp, m->m_pkthdr.csum_flags, plen,
1224                     optlen);
1225
1226                 /*
1227                  * Change the next header field of the last header in the
1228                  * unfragmentable part.
1229                  */
1230                 if (exthdrs.ip6e_rthdr) {
1231                         nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
1232                         *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
1233                 } else if (exthdrs.ip6e_dest1) {
1234                         nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
1235                         *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
1236                 } else if (exthdrs.ip6e_hbh) {
1237                         nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
1238                         *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
1239                 } else {
1240                         ip6 = mtod(m, struct ip6_hdr *);
1241                         nextproto = ip6->ip6_nxt;
1242                         ip6->ip6_nxt = IPPROTO_FRAGMENT;
1243                 }
1244
1245                 /*
1246                  * Loop through length of segment after first fragment,
1247                  * make new header and copy data of each part and link onto
1248                  * chain.
1249                  */
1250                 m0 = m;
1251                 id = htonl(ip6_randomid());
1252                 error = ip6_fragment(ifp, m, unfragpartlen, nextproto,len, id);
1253                 if (error != 0)
1254                         goto sendorfree;
1255
1256                 in6_ifstat_inc(ifp, ifs6_out_fragok);
1257         }
1258
1259         /* Remove leading garbage. */
1260 sendorfree:
1261         m = m0->m_nextpkt;
1262         m0->m_nextpkt = 0;
1263         m_freem(m0);
1264         for (; m; m = m0) {
1265                 m0 = m->m_nextpkt;
1266                 m->m_nextpkt = 0;
1267                 if (error == 0) {
1268                         /* Record statistics for this interface address. */
1269                         if (ia) {
1270                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
1271                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
1272                                     m->m_pkthdr.len);
1273                         }
1274                         if (vlan_pcp > -1)
1275                                 EVL_APPLY_PRI(m, vlan_pcp);
1276                         error = ip6_output_send(inp, ifp, origifp, m, dst, ro,
1277                             true);
1278                 } else
1279                         m_freem(m);
1280         }
1281
1282         if (error == 0)
1283                 IP6STAT_INC(ip6s_fragmented);
1284
1285 done:
1286         return (error);
1287
1288 freehdrs:
1289         m_freem(exthdrs.ip6e_hbh);      /* m_freem() checks if mbuf is NULL. */
1290         m_freem(exthdrs.ip6e_dest1);
1291         m_freem(exthdrs.ip6e_rthdr);
1292         m_freem(exthdrs.ip6e_dest2);
1293         /* FALLTHROUGH */
1294 bad:
1295         if (m)
1296                 m_freem(m);
1297         goto done;
1298 }
1299
1300 static int
1301 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
1302 {
1303         struct mbuf *m;
1304
1305         if (hlen > MCLBYTES)
1306                 return (ENOBUFS); /* XXX */
1307
1308         if (hlen > MLEN)
1309                 m = m_getcl(M_NOWAIT, MT_DATA, 0);
1310         else
1311                 m = m_get(M_NOWAIT, MT_DATA);
1312         if (m == NULL)
1313                 return (ENOBUFS);
1314         m->m_len = hlen;
1315         if (hdr)
1316                 bcopy(hdr, mtod(m, caddr_t), hlen);
1317
1318         *mp = m;
1319         return (0);
1320 }
1321
1322 /*
1323  * Insert jumbo payload option.
1324  */
1325 static int
1326 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
1327 {
1328         struct mbuf *mopt;
1329         u_char *optbuf;
1330         u_int32_t v;
1331
1332 #define JUMBOOPTLEN     8       /* length of jumbo payload option and padding */
1333
1334         /*
1335          * If there is no hop-by-hop options header, allocate new one.
1336          * If there is one but it doesn't have enough space to store the
1337          * jumbo payload option, allocate a cluster to store the whole options.
1338          * Otherwise, use it to store the options.
1339          */
1340         if (exthdrs->ip6e_hbh == NULL) {
1341                 mopt = m_get(M_NOWAIT, MT_DATA);
1342                 if (mopt == NULL)
1343                         return (ENOBUFS);
1344                 mopt->m_len = JUMBOOPTLEN;
1345                 optbuf = mtod(mopt, u_char *);
1346                 optbuf[1] = 0;  /* = ((JUMBOOPTLEN) >> 3) - 1 */
1347                 exthdrs->ip6e_hbh = mopt;
1348         } else {
1349                 struct ip6_hbh *hbh;
1350
1351                 mopt = exthdrs->ip6e_hbh;
1352                 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) {
1353                         /*
1354                          * XXX assumption:
1355                          * - exthdrs->ip6e_hbh is not referenced from places
1356                          *   other than exthdrs.
1357                          * - exthdrs->ip6e_hbh is not an mbuf chain.
1358                          */
1359                         int oldoptlen = mopt->m_len;
1360                         struct mbuf *n;
1361
1362                         /*
1363                          * XXX: give up if the whole (new) hbh header does
1364                          * not fit even in an mbuf cluster.
1365                          */
1366                         if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
1367                                 return (ENOBUFS);
1368
1369                         /*
1370                          * As a consequence, we must always prepare a cluster
1371                          * at this point.
1372                          */
1373                         n = m_getcl(M_NOWAIT, MT_DATA, 0);
1374                         if (n == NULL)
1375                                 return (ENOBUFS);
1376                         n->m_len = oldoptlen + JUMBOOPTLEN;
1377                         bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
1378                             oldoptlen);
1379                         optbuf = mtod(n, caddr_t) + oldoptlen;
1380                         m_freem(mopt);
1381                         mopt = exthdrs->ip6e_hbh = n;
1382                 } else {
1383                         optbuf = mtod(mopt, u_char *) + mopt->m_len;
1384                         mopt->m_len += JUMBOOPTLEN;
1385                 }
1386                 optbuf[0] = IP6OPT_PADN;
1387                 optbuf[1] = 1;
1388
1389                 /*
1390                  * Adjust the header length according to the pad and
1391                  * the jumbo payload option.
1392                  */
1393                 hbh = mtod(mopt, struct ip6_hbh *);
1394                 hbh->ip6h_len += (JUMBOOPTLEN >> 3);
1395         }
1396
1397         /* fill in the option. */
1398         optbuf[2] = IP6OPT_JUMBO;
1399         optbuf[3] = 4;
1400         v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
1401         bcopy(&v, &optbuf[4], sizeof(u_int32_t));
1402
1403         /* finally, adjust the packet header length */
1404         exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
1405
1406         return (0);
1407 #undef JUMBOOPTLEN
1408 }
1409
1410 /*
1411  * Insert fragment header and copy unfragmentable header portions.
1412  */
1413 static int
1414 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
1415     struct ip6_frag **frghdrp)
1416 {
1417         struct mbuf *n, *mlast;
1418
1419         if (hlen > sizeof(struct ip6_hdr)) {
1420                 n = m_copym(m0, sizeof(struct ip6_hdr),
1421                     hlen - sizeof(struct ip6_hdr), M_NOWAIT);
1422                 if (n == NULL)
1423                         return (ENOBUFS);
1424                 m->m_next = n;
1425         } else
1426                 n = m;
1427
1428         /* Search for the last mbuf of unfragmentable part. */
1429         for (mlast = n; mlast->m_next; mlast = mlast->m_next)
1430                 ;
1431
1432         if (M_WRITABLE(mlast) &&
1433             M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
1434                 /* use the trailing space of the last mbuf for the fragment hdr */
1435                 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
1436                     mlast->m_len);
1437                 mlast->m_len += sizeof(struct ip6_frag);
1438                 m->m_pkthdr.len += sizeof(struct ip6_frag);
1439         } else {
1440                 /* allocate a new mbuf for the fragment header */
1441                 struct mbuf *mfrg;
1442
1443                 mfrg = m_get(M_NOWAIT, MT_DATA);
1444                 if (mfrg == NULL)
1445                         return (ENOBUFS);
1446                 mfrg->m_len = sizeof(struct ip6_frag);
1447                 *frghdrp = mtod(mfrg, struct ip6_frag *);
1448                 mlast->m_next = mfrg;
1449         }
1450
1451         return (0);
1452 }
1453
1454 /*
1455  * Calculates IPv6 path mtu for destination @dst.
1456  * Resulting MTU is stored in @mtup.
1457  *
1458  * Returns 0 on success.
1459  */
1460 static int
1461 ip6_getpmtu_ctl(u_int fibnum, const struct in6_addr *dst, u_long *mtup)
1462 {
1463         struct epoch_tracker et;
1464         struct nhop_object *nh;
1465         struct in6_addr kdst;
1466         uint32_t scopeid;
1467         int error;
1468
1469         in6_splitscope(dst, &kdst, &scopeid);
1470
1471         NET_EPOCH_ENTER(et);
1472         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1473         if (nh != NULL)
1474                 error = ip6_calcmtu(nh->nh_ifp, dst, nh->nh_mtu, mtup, NULL, 0);
1475         else
1476                 error = EHOSTUNREACH;
1477         NET_EPOCH_EXIT(et);
1478
1479         return (error);
1480 }
1481
1482 /*
1483  * Calculates IPv6 path MTU for @dst based on transmit @ifp,
1484  * and cached data in @ro_pmtu.
1485  * MTU from (successful) route lookup is saved (along with dst)
1486  * inside @ro_pmtu to avoid subsequent route lookups after packet
1487  * filter processing.
1488  *
1489  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1490  * Returns 0 on success.
1491  */
1492 static int
1493 ip6_getpmtu(struct route_in6 *ro_pmtu, int do_lookup,
1494     struct ifnet *ifp, const struct in6_addr *dst, u_long *mtup,
1495     int *alwaysfragp, u_int fibnum, u_int proto)
1496 {
1497         struct nhop_object *nh;
1498         struct in6_addr kdst;
1499         uint32_t scopeid;
1500         struct sockaddr_in6 *sa6_dst, sin6;
1501         u_long mtu;
1502
1503         NET_EPOCH_ASSERT();
1504
1505         mtu = 0;
1506         if (ro_pmtu == NULL || do_lookup) {
1507                 /*
1508                  * Here ro_pmtu has final destination address, while
1509                  * ro might represent immediate destination.
1510                  * Use ro_pmtu destination since mtu might differ.
1511                  */
1512                 if (ro_pmtu != NULL) {
1513                         sa6_dst = (struct sockaddr_in6 *)&ro_pmtu->ro_dst;
1514                         if (!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))
1515                                 ro_pmtu->ro_mtu = 0;
1516                 } else
1517                         sa6_dst = &sin6;
1518
1519                 if (ro_pmtu == NULL || ro_pmtu->ro_mtu == 0) {
1520                         bzero(sa6_dst, sizeof(*sa6_dst));
1521                         sa6_dst->sin6_family = AF_INET6;
1522                         sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
1523                         sa6_dst->sin6_addr = *dst;
1524
1525                         in6_splitscope(dst, &kdst, &scopeid);
1526                         nh = fib6_lookup(fibnum, &kdst, scopeid, NHR_NONE, 0);
1527                         if (nh != NULL) {
1528                                 mtu = nh->nh_mtu;
1529                                 if (ro_pmtu != NULL)
1530                                         ro_pmtu->ro_mtu = mtu;
1531                         }
1532                 } else
1533                         mtu = ro_pmtu->ro_mtu;
1534         }
1535
1536         if (ro_pmtu != NULL && ro_pmtu->ro_nh != NULL)
1537                 mtu = ro_pmtu->ro_nh->nh_mtu;
1538
1539         return (ip6_calcmtu(ifp, dst, mtu, mtup, alwaysfragp, proto));
1540 }
1541
1542 /*
1543  * Calculate MTU based on transmit @ifp, route mtu @rt_mtu and
1544  * hostcache data for @dst.
1545  * Stores mtu and always-frag value into @mtup and @alwaysfragp.
1546  *
1547  * Returns 0 on success.
1548  */
1549 static int
1550 ip6_calcmtu(struct ifnet *ifp, const struct in6_addr *dst, u_long rt_mtu,
1551     u_long *mtup, int *alwaysfragp, u_int proto)
1552 {
1553         u_long mtu = 0;
1554         int alwaysfrag = 0;
1555         int error = 0;
1556
1557         if (rt_mtu > 0) {
1558                 u_int32_t ifmtu;
1559                 struct in_conninfo inc;
1560
1561                 bzero(&inc, sizeof(inc));
1562                 inc.inc_flags |= INC_ISIPV6;
1563                 inc.inc6_faddr = *dst;
1564
1565                 ifmtu = IN6_LINKMTU(ifp);
1566
1567                 /* TCP is known to react to pmtu changes so skip hc */
1568                 if (proto != IPPROTO_TCP)
1569                         mtu = tcp_hc_getmtu(&inc);
1570
1571                 if (mtu)
1572                         mtu = min(mtu, rt_mtu);
1573                 else
1574                         mtu = rt_mtu;
1575                 if (mtu == 0)
1576                         mtu = ifmtu;
1577                 else if (mtu < IPV6_MMTU) {
1578                         /*
1579                          * RFC2460 section 5, last paragraph:
1580                          * if we record ICMPv6 too big message with
1581                          * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
1582                          * or smaller, with framgent header attached.
1583                          * (fragment header is needed regardless from the
1584                          * packet size, for translators to identify packets)
1585                          */
1586                         alwaysfrag = 1;
1587                         mtu = IPV6_MMTU;
1588                 }
1589         } else if (ifp) {
1590                 mtu = IN6_LINKMTU(ifp);
1591         } else
1592                 error = EHOSTUNREACH; /* XXX */
1593
1594         *mtup = mtu;
1595         if (alwaysfragp)
1596                 *alwaysfragp = alwaysfrag;
1597         return (error);
1598 }
1599
1600 /*
1601  * IP6 socket option processing.
1602  */
1603 int
1604 ip6_ctloutput(struct socket *so, struct sockopt *sopt)
1605 {
1606         int optdatalen, uproto;
1607         void *optdata;
1608         struct inpcb *inp = sotoinpcb(so);
1609         int error, optval;
1610         int level, op, optname;
1611         int optlen;
1612         struct thread *td;
1613 #ifdef  RSS
1614         uint32_t rss_bucket;
1615         int retval;
1616 #endif
1617
1618 /*
1619  * Don't use more than a quarter of mbuf clusters.  N.B.:
1620  * nmbclusters is an int, but nmbclusters * MCLBYTES may overflow
1621  * on LP64 architectures, so cast to u_long to avoid undefined
1622  * behavior.  ILP32 architectures cannot have nmbclusters
1623  * large enough to overflow for other reasons.
1624  */
1625 #define IPV6_PKTOPTIONS_MBUF_LIMIT      ((u_long)nmbclusters * MCLBYTES / 4)
1626
1627         level = sopt->sopt_level;
1628         op = sopt->sopt_dir;
1629         optname = sopt->sopt_name;
1630         optlen = sopt->sopt_valsize;
1631         td = sopt->sopt_td;
1632         error = 0;
1633         optval = 0;
1634         uproto = (int)so->so_proto->pr_protocol;
1635
1636         if (level != IPPROTO_IPV6) {
1637                 error = EINVAL;
1638
1639                 if (sopt->sopt_level == SOL_SOCKET &&
1640                     sopt->sopt_dir == SOPT_SET) {
1641                         switch (sopt->sopt_name) {
1642                         case SO_SETFIB:
1643                                 INP_WLOCK(inp);
1644                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1645                                 INP_WUNLOCK(inp);
1646                                 error = 0;
1647                                 break;
1648                         case SO_MAX_PACING_RATE:
1649 #ifdef RATELIMIT
1650                                 INP_WLOCK(inp);
1651                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1652                                 INP_WUNLOCK(inp);
1653                                 error = 0;
1654 #else
1655                                 error = EOPNOTSUPP;
1656 #endif
1657                                 break;
1658                         default:
1659                                 break;
1660                         }
1661                 }
1662         } else {                /* level == IPPROTO_IPV6 */
1663                 switch (op) {
1664                 case SOPT_SET:
1665                         switch (optname) {
1666                         case IPV6_2292PKTOPTIONS:
1667 #ifdef IPV6_PKTOPTIONS
1668                         case IPV6_PKTOPTIONS:
1669 #endif
1670                         {
1671                                 struct mbuf *m;
1672
1673                                 if (optlen > IPV6_PKTOPTIONS_MBUF_LIMIT) {
1674                                         printf("ip6_ctloutput: mbuf limit hit\n");
1675                                         error = ENOBUFS;
1676                                         break;
1677                                 }
1678
1679                                 error = soopt_getm(sopt, &m); /* XXX */
1680                                 if (error != 0)
1681                                         break;
1682                                 error = soopt_mcopyin(sopt, m); /* XXX */
1683                                 if (error != 0)
1684                                         break;
1685                                 INP_WLOCK(inp);
1686                                 error = ip6_pcbopts(&inp->in6p_outputopts, m,
1687                                     so, sopt);
1688                                 INP_WUNLOCK(inp);
1689                                 m_freem(m); /* XXX */
1690                                 break;
1691                         }
1692
1693                         /*
1694                          * Use of some Hop-by-Hop options or some
1695                          * Destination options, might require special
1696                          * privilege.  That is, normal applications
1697                          * (without special privilege) might be forbidden
1698                          * from setting certain options in outgoing packets,
1699                          * and might never see certain options in received
1700                          * packets. [RFC 2292 Section 6]
1701                          * KAME specific note:
1702                          *  KAME prevents non-privileged users from sending or
1703                          *  receiving ANY hbh/dst options in order to avoid
1704                          *  overhead of parsing options in the kernel.
1705                          */
1706                         case IPV6_RECVHOPOPTS:
1707                         case IPV6_RECVDSTOPTS:
1708                         case IPV6_RECVRTHDRDSTOPTS:
1709                                 if (td != NULL) {
1710                                         error = priv_check(td,
1711                                             PRIV_NETINET_SETHDROPTS);
1712                                         if (error)
1713                                                 break;
1714                                 }
1715                                 /* FALLTHROUGH */
1716                         case IPV6_UNICAST_HOPS:
1717                         case IPV6_HOPLIMIT:
1718
1719                         case IPV6_RECVPKTINFO:
1720                         case IPV6_RECVHOPLIMIT:
1721                         case IPV6_RECVRTHDR:
1722                         case IPV6_RECVPATHMTU:
1723                         case IPV6_RECVTCLASS:
1724                         case IPV6_RECVFLOWID:
1725 #ifdef  RSS
1726                         case IPV6_RECVRSSBUCKETID:
1727 #endif
1728                         case IPV6_V6ONLY:
1729                         case IPV6_AUTOFLOWLABEL:
1730                         case IPV6_ORIGDSTADDR:
1731                         case IPV6_BINDANY:
1732                         case IPV6_VLAN_PCP:
1733                                 if (optname == IPV6_BINDANY && td != NULL) {
1734                                         error = priv_check(td,
1735                                             PRIV_NETINET_BINDANY);
1736                                         if (error)
1737                                                 break;
1738                                 }
1739
1740                                 if (optlen != sizeof(int)) {
1741                                         error = EINVAL;
1742                                         break;
1743                                 }
1744                                 error = sooptcopyin(sopt, &optval,
1745                                         sizeof optval, sizeof optval);
1746                                 if (error)
1747                                         break;
1748                                 switch (optname) {
1749                                 case IPV6_UNICAST_HOPS:
1750                                         if (optval < -1 || optval >= 256)
1751                                                 error = EINVAL;
1752                                         else {
1753                                                 /* -1 = kernel default */
1754                                                 inp->in6p_hops = optval;
1755                                                 if ((inp->inp_vflag &
1756                                                      INP_IPV4) != 0)
1757                                                         inp->inp_ip_ttl = optval;
1758                                         }
1759                                         break;
1760 #define OPTSET(bit) \
1761 do { \
1762         INP_WLOCK(inp); \
1763         if (optval) \
1764                 inp->inp_flags |= (bit); \
1765         else \
1766                 inp->inp_flags &= ~(bit); \
1767         INP_WUNLOCK(inp); \
1768 } while (/*CONSTCOND*/ 0)
1769 #define OPTSET2292(bit) \
1770 do { \
1771         INP_WLOCK(inp); \
1772         inp->inp_flags |= IN6P_RFC2292; \
1773         if (optval) \
1774                 inp->inp_flags |= (bit); \
1775         else \
1776                 inp->inp_flags &= ~(bit); \
1777         INP_WUNLOCK(inp); \
1778 } while (/*CONSTCOND*/ 0)
1779 #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
1780
1781 #define OPTSET2_N(bit, val) do {                                        \
1782         if (val)                                                        \
1783                 inp->inp_flags2 |= bit;                                 \
1784         else                                                            \
1785                 inp->inp_flags2 &= ~bit;                                \
1786 } while (0)
1787 #define OPTSET2(bit, val) do {                                          \
1788         INP_WLOCK(inp);                                                 \
1789         OPTSET2_N(bit, val);                                            \
1790         INP_WUNLOCK(inp);                                               \
1791 } while (0)
1792 #define OPTBIT2(bit) (inp->inp_flags2 & (bit) ? 1 : 0)
1793 #define OPTSET2292_EXCLUSIVE(bit)                                       \
1794 do {                                                                    \
1795         INP_WLOCK(inp);                                                 \
1796         if (OPTBIT(IN6P_RFC2292)) {                                     \
1797                 error = EINVAL;                                         \
1798         } else {                                                        \
1799                 if (optval)                                             \
1800                         inp->inp_flags |= (bit);                        \
1801                 else                                                    \
1802                         inp->inp_flags &= ~(bit);                       \
1803         }                                                               \
1804         INP_WUNLOCK(inp);                                               \
1805 } while (/*CONSTCOND*/ 0)
1806
1807                                 case IPV6_RECVPKTINFO:
1808                                         OPTSET2292_EXCLUSIVE(IN6P_PKTINFO);
1809                                         break;
1810
1811                                 case IPV6_HOPLIMIT:
1812                                 {
1813                                         struct ip6_pktopts **optp;
1814
1815                                         /* cannot mix with RFC2292 */
1816                                         if (OPTBIT(IN6P_RFC2292)) {
1817                                                 error = EINVAL;
1818                                                 break;
1819                                         }
1820                                         INP_WLOCK(inp);
1821                                         if (inp->inp_flags & INP_DROPPED) {
1822                                                 INP_WUNLOCK(inp);
1823                                                 return (ECONNRESET);
1824                                         }
1825                                         optp = &inp->in6p_outputopts;
1826                                         error = ip6_pcbopt(IPV6_HOPLIMIT,
1827                                             (u_char *)&optval, sizeof(optval),
1828                                             optp, (td != NULL) ? td->td_ucred :
1829                                             NULL, uproto);
1830                                         INP_WUNLOCK(inp);
1831                                         break;
1832                                 }
1833
1834                                 case IPV6_RECVHOPLIMIT:
1835                                         OPTSET2292_EXCLUSIVE(IN6P_HOPLIMIT);
1836                                         break;
1837
1838                                 case IPV6_RECVHOPOPTS:
1839                                         OPTSET2292_EXCLUSIVE(IN6P_HOPOPTS);
1840                                         break;
1841
1842                                 case IPV6_RECVDSTOPTS:
1843                                         OPTSET2292_EXCLUSIVE(IN6P_DSTOPTS);
1844                                         break;
1845
1846                                 case IPV6_RECVRTHDRDSTOPTS:
1847                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDRDSTOPTS);
1848                                         break;
1849
1850                                 case IPV6_RECVRTHDR:
1851                                         OPTSET2292_EXCLUSIVE(IN6P_RTHDR);
1852                                         break;
1853
1854                                 case IPV6_RECVPATHMTU:
1855                                         /*
1856                                          * We ignore this option for TCP
1857                                          * sockets.
1858                                          * (RFC3542 leaves this case
1859                                          * unspecified.)
1860                                          */
1861                                         if (uproto != IPPROTO_TCP)
1862                                                 OPTSET(IN6P_MTU);
1863                                         break;
1864
1865                                 case IPV6_RECVFLOWID:
1866                                         OPTSET2(INP_RECVFLOWID, optval);
1867                                         break;
1868
1869 #ifdef  RSS
1870                                 case IPV6_RECVRSSBUCKETID:
1871                                         OPTSET2(INP_RECVRSSBUCKETID, optval);
1872                                         break;
1873 #endif
1874
1875                                 case IPV6_V6ONLY:
1876                                         INP_WLOCK(inp);
1877                                         if (inp->inp_lport ||
1878                                             !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
1879                                                 /*
1880                                                  * The socket is already bound.
1881                                                  */
1882                                                 INP_WUNLOCK(inp);
1883                                                 error = EINVAL;
1884                                                 break;
1885                                         }
1886                                         if (optval) {
1887                                                 inp->inp_flags |= IN6P_IPV6_V6ONLY;
1888                                                 inp->inp_vflag &= ~INP_IPV4;
1889                                         } else {
1890                                                 inp->inp_flags &= ~IN6P_IPV6_V6ONLY;
1891                                                 inp->inp_vflag |= INP_IPV4;
1892                                         }
1893                                         INP_WUNLOCK(inp);
1894                                         break;
1895                                 case IPV6_RECVTCLASS:
1896                                         /* cannot mix with RFC2292 XXX */
1897                                         OPTSET2292_EXCLUSIVE(IN6P_TCLASS);
1898                                         break;
1899                                 case IPV6_AUTOFLOWLABEL:
1900                                         OPTSET(IN6P_AUTOFLOWLABEL);
1901                                         break;
1902
1903                                 case IPV6_ORIGDSTADDR:
1904                                         OPTSET2(INP_ORIGDSTADDR, optval);
1905                                         break;
1906                                 case IPV6_BINDANY:
1907                                         OPTSET(INP_BINDANY);
1908                                         break;
1909                                 case IPV6_VLAN_PCP:
1910                                         if ((optval >= -1) && (optval <=
1911                                             (INP_2PCP_MASK >> INP_2PCP_SHIFT))) {
1912                                                 if (optval == -1) {
1913                                                         INP_WLOCK(inp);
1914                                                         inp->inp_flags2 &=
1915                                                             ~(INP_2PCP_SET |
1916                                                             INP_2PCP_MASK);
1917                                                         INP_WUNLOCK(inp);
1918                                                 } else {
1919                                                         INP_WLOCK(inp);
1920                                                         inp->inp_flags2 |=
1921                                                             INP_2PCP_SET;
1922                                                         inp->inp_flags2 &=
1923                                                             ~INP_2PCP_MASK;
1924                                                         inp->inp_flags2 |=
1925                                                             optval <<
1926                                                             INP_2PCP_SHIFT;
1927                                                         INP_WUNLOCK(inp);
1928                                                 }
1929                                         } else
1930                                                 error = EINVAL;
1931                                         break;
1932                                 }
1933                                 break;
1934
1935                         case IPV6_TCLASS:
1936                         case IPV6_DONTFRAG:
1937                         case IPV6_USE_MIN_MTU:
1938                         case IPV6_PREFER_TEMPADDR:
1939                                 if (optlen != sizeof(optval)) {
1940                                         error = EINVAL;
1941                                         break;
1942                                 }
1943                                 error = sooptcopyin(sopt, &optval,
1944                                         sizeof optval, sizeof optval);
1945                                 if (error)
1946                                         break;
1947                                 {
1948                                         struct ip6_pktopts **optp;
1949                                         INP_WLOCK(inp);
1950                                         if (inp->inp_flags & INP_DROPPED) {
1951                                                 INP_WUNLOCK(inp);
1952                                                 return (ECONNRESET);
1953                                         }
1954                                         optp = &inp->in6p_outputopts;
1955                                         error = ip6_pcbopt(optname,
1956                                             (u_char *)&optval, sizeof(optval),
1957                                             optp, (td != NULL) ? td->td_ucred :
1958                                             NULL, uproto);
1959                                         INP_WUNLOCK(inp);
1960                                         break;
1961                                 }
1962
1963                         case IPV6_2292PKTINFO:
1964                         case IPV6_2292HOPLIMIT:
1965                         case IPV6_2292HOPOPTS:
1966                         case IPV6_2292DSTOPTS:
1967                         case IPV6_2292RTHDR:
1968                                 /* RFC 2292 */
1969                                 if (optlen != sizeof(int)) {
1970                                         error = EINVAL;
1971                                         break;
1972                                 }
1973                                 error = sooptcopyin(sopt, &optval,
1974                                         sizeof optval, sizeof optval);
1975                                 if (error)
1976                                         break;
1977                                 switch (optname) {
1978                                 case IPV6_2292PKTINFO:
1979                                         OPTSET2292(IN6P_PKTINFO);
1980                                         break;
1981                                 case IPV6_2292HOPLIMIT:
1982                                         OPTSET2292(IN6P_HOPLIMIT);
1983                                         break;
1984                                 case IPV6_2292HOPOPTS:
1985                                         /*
1986                                          * Check super-user privilege.
1987                                          * See comments for IPV6_RECVHOPOPTS.
1988                                          */
1989                                         if (td != NULL) {
1990                                                 error = priv_check(td,
1991                                                     PRIV_NETINET_SETHDROPTS);
1992                                                 if (error)
1993                                                         return (error);
1994                                         }
1995                                         OPTSET2292(IN6P_HOPOPTS);
1996                                         break;
1997                                 case IPV6_2292DSTOPTS:
1998                                         if (td != NULL) {
1999                                                 error = priv_check(td,
2000                                                     PRIV_NETINET_SETHDROPTS);
2001                                                 if (error)
2002                                                         return (error);
2003                                         }
2004                                         OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
2005                                         break;
2006                                 case IPV6_2292RTHDR:
2007                                         OPTSET2292(IN6P_RTHDR);
2008                                         break;
2009                                 }
2010                                 break;
2011                         case IPV6_PKTINFO:
2012                         case IPV6_HOPOPTS:
2013                         case IPV6_RTHDR:
2014                         case IPV6_DSTOPTS:
2015                         case IPV6_RTHDRDSTOPTS:
2016                         case IPV6_NEXTHOP:
2017                         {
2018                                 /* new advanced API (RFC3542) */
2019                                 u_char *optbuf;
2020                                 u_char optbuf_storage[MCLBYTES];
2021                                 int optlen;
2022                                 struct ip6_pktopts **optp;
2023
2024                                 /* cannot mix with RFC2292 */
2025                                 if (OPTBIT(IN6P_RFC2292)) {
2026                                         error = EINVAL;
2027                                         break;
2028                                 }
2029
2030                                 /*
2031                                  * We only ensure valsize is not too large
2032                                  * here.  Further validation will be done
2033                                  * later.
2034                                  */
2035                                 error = sooptcopyin(sopt, optbuf_storage,
2036                                     sizeof(optbuf_storage), 0);
2037                                 if (error)
2038                                         break;
2039                                 optlen = sopt->sopt_valsize;
2040                                 optbuf = optbuf_storage;
2041                                 INP_WLOCK(inp);
2042                                 if (inp->inp_flags & INP_DROPPED) {
2043                                         INP_WUNLOCK(inp);
2044                                         return (ECONNRESET);
2045                                 }
2046                                 optp = &inp->in6p_outputopts;
2047                                 error = ip6_pcbopt(optname, optbuf, optlen,
2048                                     optp, (td != NULL) ? td->td_ucred : NULL,
2049                                     uproto);
2050                                 INP_WUNLOCK(inp);
2051                                 break;
2052                         }
2053 #undef OPTSET
2054
2055                         case IPV6_MULTICAST_IF:
2056                         case IPV6_MULTICAST_HOPS:
2057                         case IPV6_MULTICAST_LOOP:
2058                         case IPV6_JOIN_GROUP:
2059                         case IPV6_LEAVE_GROUP:
2060                         case IPV6_MSFILTER:
2061                         case MCAST_BLOCK_SOURCE:
2062                         case MCAST_UNBLOCK_SOURCE:
2063                         case MCAST_JOIN_GROUP:
2064                         case MCAST_LEAVE_GROUP:
2065                         case MCAST_JOIN_SOURCE_GROUP:
2066                         case MCAST_LEAVE_SOURCE_GROUP:
2067                                 error = ip6_setmoptions(inp, sopt);
2068                                 break;
2069
2070                         case IPV6_PORTRANGE:
2071                                 error = sooptcopyin(sopt, &optval,
2072                                     sizeof optval, sizeof optval);
2073                                 if (error)
2074                                         break;
2075
2076                                 INP_WLOCK(inp);
2077                                 switch (optval) {
2078                                 case IPV6_PORTRANGE_DEFAULT:
2079                                         inp->inp_flags &= ~(INP_LOWPORT);
2080                                         inp->inp_flags &= ~(INP_HIGHPORT);
2081                                         break;
2082
2083                                 case IPV6_PORTRANGE_HIGH:
2084                                         inp->inp_flags &= ~(INP_LOWPORT);
2085                                         inp->inp_flags |= INP_HIGHPORT;
2086                                         break;
2087
2088                                 case IPV6_PORTRANGE_LOW:
2089                                         inp->inp_flags &= ~(INP_HIGHPORT);
2090                                         inp->inp_flags |= INP_LOWPORT;
2091                                         break;
2092
2093                                 default:
2094                                         error = EINVAL;
2095                                         break;
2096                                 }
2097                                 INP_WUNLOCK(inp);
2098                                 break;
2099
2100 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2101                         case IPV6_IPSEC_POLICY:
2102                                 if (IPSEC_ENABLED(ipv6)) {
2103                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2104                                         break;
2105                                 }
2106                                 /* FALLTHROUGH */
2107 #endif /* IPSEC */
2108
2109                         default:
2110                                 error = ENOPROTOOPT;
2111                                 break;
2112                         }
2113                         break;
2114
2115                 case SOPT_GET:
2116                         switch (optname) {
2117                         case IPV6_2292PKTOPTIONS:
2118 #ifdef IPV6_PKTOPTIONS
2119                         case IPV6_PKTOPTIONS:
2120 #endif
2121                                 /*
2122                                  * RFC3542 (effectively) deprecated the
2123                                  * semantics of the 2292-style pktoptions.
2124                                  * Since it was not reliable in nature (i.e.,
2125                                  * applications had to expect the lack of some
2126                                  * information after all), it would make sense
2127                                  * to simplify this part by always returning
2128                                  * empty data.
2129                                  */
2130                                 sopt->sopt_valsize = 0;
2131                                 break;
2132
2133                         case IPV6_RECVHOPOPTS:
2134                         case IPV6_RECVDSTOPTS:
2135                         case IPV6_RECVRTHDRDSTOPTS:
2136                         case IPV6_UNICAST_HOPS:
2137                         case IPV6_RECVPKTINFO:
2138                         case IPV6_RECVHOPLIMIT:
2139                         case IPV6_RECVRTHDR:
2140                         case IPV6_RECVPATHMTU:
2141
2142                         case IPV6_V6ONLY:
2143                         case IPV6_PORTRANGE:
2144                         case IPV6_RECVTCLASS:
2145                         case IPV6_AUTOFLOWLABEL:
2146                         case IPV6_BINDANY:
2147                         case IPV6_FLOWID:
2148                         case IPV6_FLOWTYPE:
2149                         case IPV6_RECVFLOWID:
2150 #ifdef  RSS
2151                         case IPV6_RSSBUCKETID:
2152                         case IPV6_RECVRSSBUCKETID:
2153 #endif
2154                         case IPV6_VLAN_PCP:
2155                                 switch (optname) {
2156                                 case IPV6_RECVHOPOPTS:
2157                                         optval = OPTBIT(IN6P_HOPOPTS);
2158                                         break;
2159
2160                                 case IPV6_RECVDSTOPTS:
2161                                         optval = OPTBIT(IN6P_DSTOPTS);
2162                                         break;
2163
2164                                 case IPV6_RECVRTHDRDSTOPTS:
2165                                         optval = OPTBIT(IN6P_RTHDRDSTOPTS);
2166                                         break;
2167
2168                                 case IPV6_UNICAST_HOPS:
2169                                         optval = inp->in6p_hops;
2170                                         break;
2171
2172                                 case IPV6_RECVPKTINFO:
2173                                         optval = OPTBIT(IN6P_PKTINFO);
2174                                         break;
2175
2176                                 case IPV6_RECVHOPLIMIT:
2177                                         optval = OPTBIT(IN6P_HOPLIMIT);
2178                                         break;
2179
2180                                 case IPV6_RECVRTHDR:
2181                                         optval = OPTBIT(IN6P_RTHDR);
2182                                         break;
2183
2184                                 case IPV6_RECVPATHMTU:
2185                                         optval = OPTBIT(IN6P_MTU);
2186                                         break;
2187
2188                                 case IPV6_V6ONLY:
2189                                         optval = OPTBIT(IN6P_IPV6_V6ONLY);
2190                                         break;
2191
2192                                 case IPV6_PORTRANGE:
2193                                     {
2194                                         int flags;
2195                                         flags = inp->inp_flags;
2196                                         if (flags & INP_HIGHPORT)
2197                                                 optval = IPV6_PORTRANGE_HIGH;
2198                                         else if (flags & INP_LOWPORT)
2199                                                 optval = IPV6_PORTRANGE_LOW;
2200                                         else
2201                                                 optval = 0;
2202                                         break;
2203                                     }
2204                                 case IPV6_RECVTCLASS:
2205                                         optval = OPTBIT(IN6P_TCLASS);
2206                                         break;
2207
2208                                 case IPV6_AUTOFLOWLABEL:
2209                                         optval = OPTBIT(IN6P_AUTOFLOWLABEL);
2210                                         break;
2211
2212                                 case IPV6_ORIGDSTADDR:
2213                                         optval = OPTBIT2(INP_ORIGDSTADDR);
2214                                         break;
2215
2216                                 case IPV6_BINDANY:
2217                                         optval = OPTBIT(INP_BINDANY);
2218                                         break;
2219
2220                                 case IPV6_FLOWID:
2221                                         optval = inp->inp_flowid;
2222                                         break;
2223
2224                                 case IPV6_FLOWTYPE:
2225                                         optval = inp->inp_flowtype;
2226                                         break;
2227
2228                                 case IPV6_RECVFLOWID:
2229                                         optval = OPTBIT2(INP_RECVFLOWID);
2230                                         break;
2231 #ifdef  RSS
2232                                 case IPV6_RSSBUCKETID:
2233                                         retval =
2234                                             rss_hash2bucket(inp->inp_flowid,
2235                                             inp->inp_flowtype,
2236                                             &rss_bucket);
2237                                         if (retval == 0)
2238                                                 optval = rss_bucket;
2239                                         else
2240                                                 error = EINVAL;
2241                                         break;
2242
2243                                 case IPV6_RECVRSSBUCKETID:
2244                                         optval = OPTBIT2(INP_RECVRSSBUCKETID);
2245                                         break;
2246 #endif
2247
2248
2249                                 case IPV6_VLAN_PCP:
2250                                         if (OPTBIT2(INP_2PCP_SET)) {
2251                                                 optval = (inp->inp_flags2 &
2252                                                             INP_2PCP_MASK) >>
2253                                                             INP_2PCP_SHIFT;
2254                                         } else {
2255                                                 optval = -1;
2256                                         }
2257                                         break;
2258                                 }
2259
2260                                 if (error)
2261                                         break;
2262                                 error = sooptcopyout(sopt, &optval,
2263                                         sizeof optval);
2264                                 break;
2265
2266                         case IPV6_PATHMTU:
2267                         {
2268                                 u_long pmtu = 0;
2269                                 struct ip6_mtuinfo mtuinfo;
2270                                 struct in6_addr addr;
2271
2272                                 if (!(so->so_state & SS_ISCONNECTED))
2273                                         return (ENOTCONN);
2274                                 /*
2275                                  * XXX: we dot not consider the case of source
2276                                  * routing, or optional information to specify
2277                                  * the outgoing interface.
2278                                  * Copy faddr out of inp to avoid holding lock
2279                                  * on inp during route lookup.
2280                                  */
2281                                 INP_RLOCK(inp);
2282                                 bcopy(&inp->in6p_faddr, &addr, sizeof(addr));
2283                                 INP_RUNLOCK(inp);
2284                                 error = ip6_getpmtu_ctl(so->so_fibnum,
2285                                     &addr, &pmtu);
2286                                 if (error)
2287                                         break;
2288                                 if (pmtu > IPV6_MAXPACKET)
2289                                         pmtu = IPV6_MAXPACKET;
2290
2291                                 bzero(&mtuinfo, sizeof(mtuinfo));
2292                                 mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
2293                                 optdata = (void *)&mtuinfo;
2294                                 optdatalen = sizeof(mtuinfo);
2295                                 error = sooptcopyout(sopt, optdata,
2296                                     optdatalen);
2297                                 break;
2298                         }
2299
2300                         case IPV6_2292PKTINFO:
2301                         case IPV6_2292HOPLIMIT:
2302                         case IPV6_2292HOPOPTS:
2303                         case IPV6_2292RTHDR:
2304                         case IPV6_2292DSTOPTS:
2305                                 switch (optname) {
2306                                 case IPV6_2292PKTINFO:
2307                                         optval = OPTBIT(IN6P_PKTINFO);
2308                                         break;
2309                                 case IPV6_2292HOPLIMIT:
2310                                         optval = OPTBIT(IN6P_HOPLIMIT);
2311                                         break;
2312                                 case IPV6_2292HOPOPTS:
2313                                         optval = OPTBIT(IN6P_HOPOPTS);
2314                                         break;
2315                                 case IPV6_2292RTHDR:
2316                                         optval = OPTBIT(IN6P_RTHDR);
2317                                         break;
2318                                 case IPV6_2292DSTOPTS:
2319                                         optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
2320                                         break;
2321                                 }
2322                                 error = sooptcopyout(sopt, &optval,
2323                                     sizeof optval);
2324                                 break;
2325                         case IPV6_PKTINFO:
2326                         case IPV6_HOPOPTS:
2327                         case IPV6_RTHDR:
2328                         case IPV6_DSTOPTS:
2329                         case IPV6_RTHDRDSTOPTS:
2330                         case IPV6_NEXTHOP:
2331                         case IPV6_TCLASS:
2332                         case IPV6_DONTFRAG:
2333                         case IPV6_USE_MIN_MTU:
2334                         case IPV6_PREFER_TEMPADDR:
2335                                 error = ip6_getpcbopt(inp, optname, sopt);
2336                                 break;
2337
2338                         case IPV6_MULTICAST_IF:
2339                         case IPV6_MULTICAST_HOPS:
2340                         case IPV6_MULTICAST_LOOP:
2341                         case IPV6_MSFILTER:
2342                                 error = ip6_getmoptions(inp, sopt);
2343                                 break;
2344
2345 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
2346                         case IPV6_IPSEC_POLICY:
2347                                 if (IPSEC_ENABLED(ipv6)) {
2348                                         error = IPSEC_PCBCTL(ipv6, inp, sopt);
2349                                         break;
2350                                 }
2351                                 /* FALLTHROUGH */
2352 #endif /* IPSEC */
2353                         default:
2354                                 error = ENOPROTOOPT;
2355                                 break;
2356                         }
2357                         break;
2358                 }
2359         }
2360         return (error);
2361 }
2362
2363 int
2364 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
2365 {
2366         int error = 0, optval, optlen;
2367         const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
2368         struct inpcb *inp = sotoinpcb(so);
2369         int level, op, optname;
2370
2371         level = sopt->sopt_level;
2372         op = sopt->sopt_dir;
2373         optname = sopt->sopt_name;
2374         optlen = sopt->sopt_valsize;
2375
2376         if (level != IPPROTO_IPV6) {
2377                 return (EINVAL);
2378         }
2379
2380         switch (optname) {
2381         case IPV6_CHECKSUM:
2382                 /*
2383                  * For ICMPv6 sockets, no modification allowed for checksum
2384                  * offset, permit "no change" values to help existing apps.
2385                  *
2386                  * RFC3542 says: "An attempt to set IPV6_CHECKSUM
2387                  * for an ICMPv6 socket will fail."
2388                  * The current behavior does not meet RFC3542.
2389                  */
2390                 switch (op) {
2391                 case SOPT_SET:
2392                         if (optlen != sizeof(int)) {
2393                                 error = EINVAL;
2394                                 break;
2395                         }
2396                         error = sooptcopyin(sopt, &optval, sizeof(optval),
2397                                             sizeof(optval));
2398                         if (error)
2399                                 break;
2400                         if (optval < -1 || (optval % 2) != 0) {
2401                                 /*
2402                                  * The API assumes non-negative even offset
2403                                  * values or -1 as a special value.
2404                                  */
2405                                 error = EINVAL;
2406                         } else if (inp->inp_ip_p == IPPROTO_ICMPV6) {
2407                                 if (optval != icmp6off)
2408                                         error = EINVAL;
2409                         } else
2410                                 inp->in6p_cksum = optval;
2411                         break;
2412
2413                 case SOPT_GET:
2414                         if (inp->inp_ip_p == IPPROTO_ICMPV6)
2415                                 optval = icmp6off;
2416                         else
2417                                 optval = inp->in6p_cksum;
2418
2419                         error = sooptcopyout(sopt, &optval, sizeof(optval));
2420                         break;
2421
2422                 default:
2423                         error = EINVAL;
2424                         break;
2425                 }
2426                 break;
2427
2428         default:
2429                 error = ENOPROTOOPT;
2430                 break;
2431         }
2432
2433         return (error);
2434 }
2435
2436 /*
2437  * Set up IP6 options in pcb for insertion in output packets or
2438  * specifying behavior of outgoing packets.
2439  */
2440 static int
2441 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
2442     struct socket *so, struct sockopt *sopt)
2443 {
2444         struct ip6_pktopts *opt = *pktopt;
2445         int error = 0;
2446         struct thread *td = sopt->sopt_td;
2447         struct epoch_tracker et;
2448
2449         /* turn off any old options. */
2450         if (opt) {
2451 #ifdef DIAGNOSTIC
2452                 if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
2453                     opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
2454                     opt->ip6po_rhinfo.ip6po_rhi_rthdr)
2455                         printf("ip6_pcbopts: all specified options are cleared.\n");
2456 #endif
2457                 ip6_clearpktopts(opt, -1);
2458         } else {
2459                 opt = malloc(sizeof(*opt), M_IP6OPT, M_NOWAIT);
2460                 if (opt == NULL)
2461                         return (ENOMEM);
2462         }
2463         *pktopt = NULL;
2464
2465         if (!m || m->m_len == 0) {
2466                 /*
2467                  * Only turning off any previous options, regardless of
2468                  * whether the opt is just created or given.
2469                  */
2470                 free(opt, M_IP6OPT);
2471                 return (0);
2472         }
2473
2474         /*  set options specified by user. */
2475         NET_EPOCH_ENTER(et);
2476         if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
2477             td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
2478                 ip6_clearpktopts(opt, -1); /* XXX: discard all options */
2479                 free(opt, M_IP6OPT);
2480                 NET_EPOCH_EXIT(et);
2481                 return (error);
2482         }
2483         NET_EPOCH_EXIT(et);
2484         *pktopt = opt;
2485         return (0);
2486 }
2487
2488 /*
2489  * initialize ip6_pktopts.  beware that there are non-zero default values in
2490  * the struct.
2491  */
2492 void
2493 ip6_initpktopts(struct ip6_pktopts *opt)
2494 {
2495
2496         bzero(opt, sizeof(*opt));
2497         opt->ip6po_hlim = -1;   /* -1 means default hop limit */
2498         opt->ip6po_tclass = -1; /* -1 means default traffic class */
2499         opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
2500         opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
2501 }
2502
2503 static int
2504 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
2505     struct ucred *cred, int uproto)
2506 {
2507         struct epoch_tracker et;
2508         struct ip6_pktopts *opt;
2509         int ret;
2510
2511         if (*pktopt == NULL) {
2512                 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
2513                     M_NOWAIT);
2514                 if (*pktopt == NULL)
2515                         return (ENOBUFS);
2516                 ip6_initpktopts(*pktopt);
2517         }
2518         opt = *pktopt;
2519
2520         NET_EPOCH_ENTER(et);
2521         ret = ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto);
2522         NET_EPOCH_EXIT(et);
2523
2524         return (ret);
2525 }
2526
2527 #define GET_PKTOPT_VAR(field, lenexpr) do {                             \
2528         if (pktopt && pktopt->field) {                                  \
2529                 INP_RUNLOCK(inp);                                       \
2530                 optdata = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK); \
2531                 malloc_optdata = true;                                  \
2532                 INP_RLOCK(inp);                                         \
2533                 if (inp->inp_flags & INP_DROPPED) {                     \
2534                         INP_RUNLOCK(inp);                               \
2535                         free(optdata, M_TEMP);                          \
2536                         return (ECONNRESET);                            \
2537                 }                                                       \
2538                 pktopt = inp->in6p_outputopts;                          \
2539                 if (pktopt && pktopt->field) {                          \
2540                         optdatalen = min(lenexpr, sopt->sopt_valsize);  \
2541                         bcopy(pktopt->field, optdata, optdatalen);      \
2542                 } else {                                                \
2543                         free(optdata, M_TEMP);                          \
2544                         optdata = NULL;                                 \
2545                         malloc_optdata = false;                         \
2546                 }                                                       \
2547         }                                                               \
2548 } while(0)
2549
2550 #define GET_PKTOPT_EXT_HDR(field) GET_PKTOPT_VAR(field,                 \
2551         (((struct ip6_ext *)pktopt->field)->ip6e_len + 1) << 3)
2552
2553 #define GET_PKTOPT_SOCKADDR(field) GET_PKTOPT_VAR(field,                \
2554         pktopt->field->sa_len)
2555
2556 static int
2557 ip6_getpcbopt(struct inpcb *inp, int optname, struct sockopt *sopt)
2558 {
2559         void *optdata = NULL;
2560         bool malloc_optdata = false;
2561         int optdatalen = 0;
2562         int error = 0;
2563         struct in6_pktinfo null_pktinfo;
2564         int deftclass = 0, on;
2565         int defminmtu = IP6PO_MINMTU_MCASTONLY;
2566         int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
2567         struct ip6_pktopts *pktopt;
2568
2569         INP_RLOCK(inp);
2570         pktopt = inp->in6p_outputopts;
2571
2572         switch (optname) {
2573         case IPV6_PKTINFO:
2574                 optdata = (void *)&null_pktinfo;
2575                 if (pktopt && pktopt->ip6po_pktinfo) {
2576                         bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
2577                             sizeof(null_pktinfo));
2578                         in6_clearscope(&null_pktinfo.ipi6_addr);
2579                 } else {
2580                         /* XXX: we don't have to do this every time... */
2581                         bzero(&null_pktinfo, sizeof(null_pktinfo));
2582                 }
2583                 optdatalen = sizeof(struct in6_pktinfo);
2584                 break;
2585         case IPV6_TCLASS:
2586                 if (pktopt && pktopt->ip6po_tclass >= 0)
2587                         deftclass = pktopt->ip6po_tclass;
2588                 optdata = (void *)&deftclass;
2589                 optdatalen = sizeof(int);
2590                 break;
2591         case IPV6_HOPOPTS:
2592                 GET_PKTOPT_EXT_HDR(ip6po_hbh);
2593                 break;
2594         case IPV6_RTHDR:
2595                 GET_PKTOPT_EXT_HDR(ip6po_rthdr);
2596                 break;
2597         case IPV6_RTHDRDSTOPTS:
2598                 GET_PKTOPT_EXT_HDR(ip6po_dest1);
2599                 break;
2600         case IPV6_DSTOPTS:
2601                 GET_PKTOPT_EXT_HDR(ip6po_dest2);
2602                 break;
2603         case IPV6_NEXTHOP:
2604                 GET_PKTOPT_SOCKADDR(ip6po_nexthop);
2605                 break;
2606         case IPV6_USE_MIN_MTU:
2607                 if (pktopt)
2608                         defminmtu = pktopt->ip6po_minmtu;
2609                 optdata = (void *)&defminmtu;
2610                 optdatalen = sizeof(int);
2611                 break;
2612         case IPV6_DONTFRAG:
2613                 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
2614                         on = 1;
2615                 else
2616                         on = 0;
2617                 optdata = (void *)&on;
2618                 optdatalen = sizeof(on);
2619                 break;
2620         case IPV6_PREFER_TEMPADDR:
2621                 if (pktopt)
2622                         defpreftemp = pktopt->ip6po_prefer_tempaddr;
2623                 optdata = (void *)&defpreftemp;
2624                 optdatalen = sizeof(int);
2625                 break;
2626         default:                /* should not happen */
2627 #ifdef DIAGNOSTIC
2628                 panic("ip6_getpcbopt: unexpected option\n");
2629 #endif
2630                 INP_RUNLOCK(inp);
2631                 return (ENOPROTOOPT);
2632         }
2633         INP_RUNLOCK(inp);
2634
2635         error = sooptcopyout(sopt, optdata, optdatalen);
2636         if (malloc_optdata)
2637                 free(optdata, M_TEMP);
2638
2639         return (error);
2640 }
2641
2642 void
2643 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
2644 {
2645         if (pktopt == NULL)
2646                 return;
2647
2648         if (optname == -1 || optname == IPV6_PKTINFO) {
2649                 if (pktopt->ip6po_pktinfo)
2650                         free(pktopt->ip6po_pktinfo, M_IP6OPT);
2651                 pktopt->ip6po_pktinfo = NULL;
2652         }
2653         if (optname == -1 || optname == IPV6_HOPLIMIT)
2654                 pktopt->ip6po_hlim = -1;
2655         if (optname == -1 || optname == IPV6_TCLASS)
2656                 pktopt->ip6po_tclass = -1;
2657         if (optname == -1 || optname == IPV6_NEXTHOP) {
2658                 if (pktopt->ip6po_nextroute.ro_nh) {
2659                         NH_FREE(pktopt->ip6po_nextroute.ro_nh);
2660                         pktopt->ip6po_nextroute.ro_nh = NULL;
2661                 }
2662                 if (pktopt->ip6po_nexthop)
2663                         free(pktopt->ip6po_nexthop, M_IP6OPT);
2664                 pktopt->ip6po_nexthop = NULL;
2665         }
2666         if (optname == -1 || optname == IPV6_HOPOPTS) {
2667                 if (pktopt->ip6po_hbh)
2668                         free(pktopt->ip6po_hbh, M_IP6OPT);
2669                 pktopt->ip6po_hbh = NULL;
2670         }
2671         if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
2672                 if (pktopt->ip6po_dest1)
2673                         free(pktopt->ip6po_dest1, M_IP6OPT);
2674                 pktopt->ip6po_dest1 = NULL;
2675         }
2676         if (optname == -1 || optname == IPV6_RTHDR) {
2677                 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
2678                         free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT);
2679                 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
2680                 if (pktopt->ip6po_route.ro_nh) {
2681                         NH_FREE(pktopt->ip6po_route.ro_nh);
2682                         pktopt->ip6po_route.ro_nh = NULL;
2683                 }
2684         }
2685         if (optname == -1 || optname == IPV6_DSTOPTS) {
2686                 if (pktopt->ip6po_dest2)
2687                         free(pktopt->ip6po_dest2, M_IP6OPT);
2688                 pktopt->ip6po_dest2 = NULL;
2689         }
2690 }
2691
2692 #define PKTOPT_EXTHDRCPY(type) \
2693 do {\
2694         if (src->type) {\
2695                 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
2696                 dst->type = malloc(hlen, M_IP6OPT, canwait);\
2697                 if (dst->type == NULL)\
2698                         goto bad;\
2699                 bcopy(src->type, dst->type, hlen);\
2700         }\
2701 } while (/*CONSTCOND*/ 0)
2702
2703 static int
2704 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
2705 {
2706         if (dst == NULL || src == NULL)  {
2707                 printf("ip6_clearpktopts: invalid argument\n");
2708                 return (EINVAL);
2709         }
2710
2711         dst->ip6po_hlim = src->ip6po_hlim;
2712         dst->ip6po_tclass = src->ip6po_tclass;
2713         dst->ip6po_flags = src->ip6po_flags;
2714         dst->ip6po_minmtu = src->ip6po_minmtu;
2715         dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
2716         if (src->ip6po_pktinfo) {
2717                 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
2718                     M_IP6OPT, canwait);
2719                 if (dst->ip6po_pktinfo == NULL)
2720                         goto bad;
2721                 *dst->ip6po_pktinfo = *src->ip6po_pktinfo;
2722         }
2723         if (src->ip6po_nexthop) {
2724                 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
2725                     M_IP6OPT, canwait);
2726                 if (dst->ip6po_nexthop == NULL)
2727                         goto bad;
2728                 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
2729                     src->ip6po_nexthop->sa_len);
2730         }
2731         PKTOPT_EXTHDRCPY(ip6po_hbh);
2732         PKTOPT_EXTHDRCPY(ip6po_dest1);
2733         PKTOPT_EXTHDRCPY(ip6po_dest2);
2734         PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
2735         return (0);
2736
2737   bad:
2738         ip6_clearpktopts(dst, -1);
2739         return (ENOBUFS);
2740 }
2741 #undef PKTOPT_EXTHDRCPY
2742
2743 struct ip6_pktopts *
2744 ip6_copypktopts(struct ip6_pktopts *src, int canwait)
2745 {
2746         int error;
2747         struct ip6_pktopts *dst;
2748
2749         dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
2750         if (dst == NULL)
2751                 return (NULL);
2752         ip6_initpktopts(dst);
2753
2754         if ((error = copypktopts(dst, src, canwait)) != 0) {
2755                 free(dst, M_IP6OPT);
2756                 return (NULL);
2757         }
2758
2759         return (dst);
2760 }
2761
2762 void
2763 ip6_freepcbopts(struct ip6_pktopts *pktopt)
2764 {
2765         if (pktopt == NULL)
2766                 return;
2767
2768         ip6_clearpktopts(pktopt, -1);
2769
2770         free(pktopt, M_IP6OPT);
2771 }
2772
2773 /*
2774  * Set IPv6 outgoing packet options based on advanced API.
2775  */
2776 int
2777 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
2778     struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
2779 {
2780         struct cmsghdr *cm = NULL;
2781
2782         if (control == NULL || opt == NULL)
2783                 return (EINVAL);
2784
2785         /*
2786          * ip6_setpktopt can call ifnet_byindex(), so it's imperative that we
2787          * are in the network epoch here.
2788          */
2789         NET_EPOCH_ASSERT();
2790
2791         ip6_initpktopts(opt);
2792         if (stickyopt) {
2793                 int error;
2794
2795                 /*
2796                  * If stickyopt is provided, make a local copy of the options
2797                  * for this particular packet, then override them by ancillary
2798                  * objects.
2799                  * XXX: copypktopts() does not copy the cached route to a next
2800                  * hop (if any).  This is not very good in terms of efficiency,
2801                  * but we can allow this since this option should be rarely
2802                  * used.
2803                  */
2804                 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0)
2805                         return (error);
2806         }
2807
2808         /*
2809          * XXX: Currently, we assume all the optional information is stored
2810          * in a single mbuf.
2811          */
2812         if (control->m_next)
2813                 return (EINVAL);
2814
2815         for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
2816             control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
2817                 int error;
2818
2819                 if (control->m_len < CMSG_LEN(0))
2820                         return (EINVAL);
2821
2822                 cm = mtod(control, struct cmsghdr *);
2823                 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
2824                         return (EINVAL);
2825                 if (cm->cmsg_level != IPPROTO_IPV6)
2826                         continue;
2827
2828                 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
2829                     cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
2830                 if (error)
2831                         return (error);
2832         }
2833
2834         return (0);
2835 }
2836
2837 /*
2838  * Set a particular packet option, as a sticky option or an ancillary data
2839  * item.  "len" can be 0 only when it's a sticky option.
2840  * We have 4 cases of combination of "sticky" and "cmsg":
2841  * "sticky=0, cmsg=0": impossible
2842  * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
2843  * "sticky=1, cmsg=0": RFC3542 socket option
2844  * "sticky=1, cmsg=1": RFC2292 socket option
2845  */
2846 static int
2847 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
2848     struct ucred *cred, int sticky, int cmsg, int uproto)
2849 {
2850         int minmtupolicy, preftemp;
2851         int error;
2852
2853         NET_EPOCH_ASSERT();
2854
2855         if (!sticky && !cmsg) {
2856 #ifdef DIAGNOSTIC
2857                 printf("ip6_setpktopt: impossible case\n");
2858 #endif
2859                 return (EINVAL);
2860         }
2861
2862         /*
2863          * IPV6_2292xxx is for backward compatibility to RFC2292, and should
2864          * not be specified in the context of RFC3542.  Conversely,
2865          * RFC3542 types should not be specified in the context of RFC2292.
2866          */
2867         if (!cmsg) {
2868                 switch (optname) {
2869                 case IPV6_2292PKTINFO:
2870                 case IPV6_2292HOPLIMIT:
2871                 case IPV6_2292NEXTHOP:
2872                 case IPV6_2292HOPOPTS:
2873                 case IPV6_2292DSTOPTS:
2874                 case IPV6_2292RTHDR:
2875                 case IPV6_2292PKTOPTIONS:
2876                         return (ENOPROTOOPT);
2877                 }
2878         }
2879         if (sticky && cmsg) {
2880                 switch (optname) {
2881                 case IPV6_PKTINFO:
2882                 case IPV6_HOPLIMIT:
2883                 case IPV6_NEXTHOP:
2884                 case IPV6_HOPOPTS:
2885                 case IPV6_DSTOPTS:
2886                 case IPV6_RTHDRDSTOPTS:
2887                 case IPV6_RTHDR:
2888                 case IPV6_USE_MIN_MTU:
2889                 case IPV6_DONTFRAG:
2890                 case IPV6_TCLASS:
2891                 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
2892                         return (ENOPROTOOPT);
2893                 }
2894         }
2895
2896         switch (optname) {
2897         case IPV6_2292PKTINFO:
2898         case IPV6_PKTINFO:
2899         {
2900                 struct ifnet *ifp = NULL;
2901                 struct in6_pktinfo *pktinfo;
2902
2903                 if (len != sizeof(struct in6_pktinfo))
2904                         return (EINVAL);
2905
2906                 pktinfo = (struct in6_pktinfo *)buf;
2907
2908                 /*
2909                  * An application can clear any sticky IPV6_PKTINFO option by
2910                  * doing a "regular" setsockopt with ipi6_addr being
2911                  * in6addr_any and ipi6_ifindex being zero.
2912                  * [RFC 3542, Section 6]
2913                  */
2914                 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
2915                     pktinfo->ipi6_ifindex == 0 &&
2916                     IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2917                         ip6_clearpktopts(opt, optname);
2918                         break;
2919                 }
2920
2921                 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
2922                     sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2923                         return (EINVAL);
2924                 }
2925                 if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
2926                         return (EINVAL);
2927                 /* validate the interface index if specified. */
2928                 if (pktinfo->ipi6_ifindex) {
2929                         ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
2930                         if (ifp == NULL)
2931                                 return (ENXIO);
2932                 }
2933                 if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
2934                     (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
2935                         return (ENETDOWN);
2936
2937                 if (ifp != NULL &&
2938                     !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
2939                         struct in6_ifaddr *ia;
2940
2941                         in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
2942                         ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
2943                         if (ia == NULL)
2944                                 return (EADDRNOTAVAIL);
2945                         ifa_free(&ia->ia_ifa);
2946                 }
2947                 /*
2948                  * We store the address anyway, and let in6_selectsrc()
2949                  * validate the specified address.  This is because ipi6_addr
2950                  * may not have enough information about its scope zone, and
2951                  * we may need additional information (such as outgoing
2952                  * interface or the scope zone of a destination address) to
2953                  * disambiguate the scope.
2954                  * XXX: the delay of the validation may confuse the
2955                  * application when it is used as a sticky option.
2956                  */
2957                 if (opt->ip6po_pktinfo == NULL) {
2958                         opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
2959                             M_IP6OPT, M_NOWAIT);
2960                         if (opt->ip6po_pktinfo == NULL)
2961                                 return (ENOBUFS);
2962                 }
2963                 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
2964                 break;
2965         }
2966
2967         case IPV6_2292HOPLIMIT:
2968         case IPV6_HOPLIMIT:
2969         {
2970                 int *hlimp;
2971
2972                 /*
2973                  * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
2974                  * to simplify the ordering among hoplimit options.
2975                  */
2976                 if (optname == IPV6_HOPLIMIT && sticky)
2977                         return (ENOPROTOOPT);
2978
2979                 if (len != sizeof(int))
2980                         return (EINVAL);
2981                 hlimp = (int *)buf;
2982                 if (*hlimp < -1 || *hlimp > 255)
2983                         return (EINVAL);
2984
2985                 opt->ip6po_hlim = *hlimp;
2986                 break;
2987         }
2988
2989         case IPV6_TCLASS:
2990         {
2991                 int tclass;
2992
2993                 if (len != sizeof(int))
2994                         return (EINVAL);
2995                 tclass = *(int *)buf;
2996                 if (tclass < -1 || tclass > 255)
2997                         return (EINVAL);
2998
2999                 opt->ip6po_tclass = tclass;
3000                 break;
3001         }
3002
3003         case IPV6_2292NEXTHOP:
3004         case IPV6_NEXTHOP:
3005                 if (cred != NULL) {
3006                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3007                         if (error)
3008                                 return (error);
3009                 }
3010
3011                 if (len == 0) { /* just remove the option */
3012                         ip6_clearpktopts(opt, IPV6_NEXTHOP);
3013                         break;
3014                 }
3015
3016                 /* check if cmsg_len is large enough for sa_len */
3017                 if (len < sizeof(struct sockaddr) || len < *buf)
3018                         return (EINVAL);
3019
3020                 switch (((struct sockaddr *)buf)->sa_family) {
3021                 case AF_INET6:
3022                 {
3023                         struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
3024                         int error;
3025
3026                         if (sa6->sin6_len != sizeof(struct sockaddr_in6))
3027                                 return (EINVAL);
3028
3029                         if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
3030                             IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
3031                                 return (EINVAL);
3032                         }
3033                         if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
3034                             != 0) {
3035                                 return (error);
3036                         }
3037                         break;
3038                 }
3039                 case AF_LINK:   /* should eventually be supported */
3040                 default:
3041                         return (EAFNOSUPPORT);
3042                 }
3043
3044                 /* turn off the previous option, then set the new option. */
3045                 ip6_clearpktopts(opt, IPV6_NEXTHOP);
3046                 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
3047                 if (opt->ip6po_nexthop == NULL)
3048                         return (ENOBUFS);
3049                 bcopy(buf, opt->ip6po_nexthop, *buf);
3050                 break;
3051
3052         case IPV6_2292HOPOPTS:
3053         case IPV6_HOPOPTS:
3054         {
3055                 struct ip6_hbh *hbh;
3056                 int hbhlen;
3057
3058                 /*
3059                  * XXX: We don't allow a non-privileged user to set ANY HbH
3060                  * options, since per-option restriction has too much
3061                  * overhead.
3062                  */
3063                 if (cred != NULL) {
3064                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3065                         if (error)
3066                                 return (error);
3067                 }
3068
3069                 if (len == 0) {
3070                         ip6_clearpktopts(opt, IPV6_HOPOPTS);
3071                         break;  /* just remove the option */
3072                 }
3073
3074                 /* message length validation */
3075                 if (len < sizeof(struct ip6_hbh))
3076                         return (EINVAL);
3077                 hbh = (struct ip6_hbh *)buf;
3078                 hbhlen = (hbh->ip6h_len + 1) << 3;
3079                 if (len != hbhlen)
3080                         return (EINVAL);
3081
3082                 /* turn off the previous option, then set the new option. */
3083                 ip6_clearpktopts(opt, IPV6_HOPOPTS);
3084                 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
3085                 if (opt->ip6po_hbh == NULL)
3086                         return (ENOBUFS);
3087                 bcopy(hbh, opt->ip6po_hbh, hbhlen);
3088
3089                 break;
3090         }
3091
3092         case IPV6_2292DSTOPTS:
3093         case IPV6_DSTOPTS:
3094         case IPV6_RTHDRDSTOPTS:
3095         {
3096                 struct ip6_dest *dest, **newdest = NULL;
3097                 int destlen;
3098
3099                 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
3100                         error = priv_check_cred(cred, PRIV_NETINET_SETHDROPTS);
3101                         if (error)
3102                                 return (error);
3103                 }
3104
3105                 if (len == 0) {
3106                         ip6_clearpktopts(opt, optname);
3107                         break;  /* just remove the option */
3108                 }
3109
3110                 /* message length validation */
3111                 if (len < sizeof(struct ip6_dest))
3112                         return (EINVAL);
3113                 dest = (struct ip6_dest *)buf;
3114                 destlen = (dest->ip6d_len + 1) << 3;
3115                 if (len != destlen)
3116                         return (EINVAL);
3117
3118                 /*
3119                  * Determine the position that the destination options header
3120                  * should be inserted; before or after the routing header.
3121                  */
3122                 switch (optname) {
3123                 case IPV6_2292DSTOPTS:
3124                         /*
3125                          * The old advacned API is ambiguous on this point.
3126                          * Our approach is to determine the position based
3127                          * according to the existence of a routing header.
3128                          * Note, however, that this depends on the order of the
3129                          * extension headers in the ancillary data; the 1st
3130                          * part of the destination options header must appear
3131                          * before the routing header in the ancillary data,
3132                          * too.
3133                          * RFC3542 solved the ambiguity by introducing
3134                          * separate ancillary data or option types.
3135                          */
3136                         if (opt->ip6po_rthdr == NULL)
3137                                 newdest = &opt->ip6po_dest1;
3138                         else
3139                                 newdest = &opt->ip6po_dest2;
3140                         break;
3141                 case IPV6_RTHDRDSTOPTS:
3142                         newdest = &opt->ip6po_dest1;
3143                         break;
3144                 case IPV6_DSTOPTS:
3145                         newdest = &opt->ip6po_dest2;
3146                         break;
3147                 }
3148
3149                 /* turn off the previous option, then set the new option. */
3150                 ip6_clearpktopts(opt, optname);
3151                 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
3152                 if (*newdest == NULL)
3153                         return (ENOBUFS);
3154                 bcopy(dest, *newdest, destlen);
3155
3156                 break;
3157         }
3158
3159         case IPV6_2292RTHDR:
3160         case IPV6_RTHDR:
3161         {
3162                 struct ip6_rthdr *rth;
3163                 int rthlen;
3164
3165                 if (len == 0) {
3166                         ip6_clearpktopts(opt, IPV6_RTHDR);
3167                         break;  /* just remove the option */
3168                 }
3169
3170                 /* message length validation */
3171                 if (len < sizeof(struct ip6_rthdr))
3172                         return (EINVAL);
3173                 rth = (struct ip6_rthdr *)buf;
3174                 rthlen = (rth->ip6r_len + 1) << 3;
3175                 if (len != rthlen)
3176                         return (EINVAL);
3177
3178                 switch (rth->ip6r_type) {
3179                 case IPV6_RTHDR_TYPE_0:
3180                         if (rth->ip6r_len == 0) /* must contain one addr */
3181                                 return (EINVAL);
3182                         if (rth->ip6r_len % 2) /* length must be even */
3183                                 return (EINVAL);
3184                         if (rth->ip6r_len / 2 != rth->ip6r_segleft)
3185                                 return (EINVAL);
3186                         break;
3187                 default:
3188                         return (EINVAL);        /* not supported */
3189                 }
3190
3191                 /* turn off the previous option */
3192                 ip6_clearpktopts(opt, IPV6_RTHDR);
3193                 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
3194                 if (opt->ip6po_rthdr == NULL)
3195                         return (ENOBUFS);
3196                 bcopy(rth, opt->ip6po_rthdr, rthlen);
3197
3198                 break;
3199         }
3200
3201         case IPV6_USE_MIN_MTU:
3202                 if (len != sizeof(int))
3203                         return (EINVAL);
3204                 minmtupolicy = *(int *)buf;
3205                 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
3206                     minmtupolicy != IP6PO_MINMTU_DISABLE &&
3207                     minmtupolicy != IP6PO_MINMTU_ALL) {
3208                         return (EINVAL);
3209                 }
3210                 opt->ip6po_minmtu = minmtupolicy;
3211                 break;
3212
3213         case IPV6_DONTFRAG:
3214                 if (len != sizeof(int))
3215                         return (EINVAL);
3216
3217                 if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
3218                         /*
3219                          * we ignore this option for TCP sockets.
3220                          * (RFC3542 leaves this case unspecified.)
3221                          */
3222                         opt->ip6po_flags &= ~IP6PO_DONTFRAG;
3223                 } else
3224                         opt->ip6po_flags |= IP6PO_DONTFRAG;
3225                 break;
3226
3227         case IPV6_PREFER_TEMPADDR:
3228                 if (len != sizeof(int))
3229                         return (EINVAL);
3230                 preftemp = *(int *)buf;
3231                 if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
3232                     preftemp != IP6PO_TEMPADDR_NOTPREFER &&
3233                     preftemp != IP6PO_TEMPADDR_PREFER) {
3234                         return (EINVAL);
3235                 }
3236                 opt->ip6po_prefer_tempaddr = preftemp;
3237                 break;
3238
3239         default:
3240                 return (ENOPROTOOPT);
3241         } /* end of switch */
3242
3243         return (0);
3244 }
3245
3246 /*
3247  * Routine called from ip6_output() to loop back a copy of an IP6 multicast
3248  * packet to the input queue of a specified interface.  Note that this
3249  * calls the output routine of the loopback "driver", but with an interface
3250  * pointer that might NOT be &loif -- easier than replicating that code here.
3251  */
3252 void
3253 ip6_mloopback(struct ifnet *ifp, struct mbuf *m)
3254 {
3255         struct mbuf *copym;
3256         struct ip6_hdr *ip6;
3257
3258         copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
3259         if (copym == NULL)
3260                 return;
3261
3262         /*
3263          * Make sure to deep-copy IPv6 header portion in case the data
3264          * is in an mbuf cluster, so that we can safely override the IPv6
3265          * header portion later.
3266          */
3267         if (!M_WRITABLE(copym) ||
3268             copym->m_len < sizeof(struct ip6_hdr)) {
3269                 copym = m_pullup(copym, sizeof(struct ip6_hdr));
3270                 if (copym == NULL)
3271                         return;
3272         }
3273         ip6 = mtod(copym, struct ip6_hdr *);
3274         /*
3275          * clear embedded scope identifiers if necessary.
3276          * in6_clearscope will touch the addresses only when necessary.
3277          */
3278         in6_clearscope(&ip6->ip6_src);
3279         in6_clearscope(&ip6->ip6_dst);
3280         if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
3281                 copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
3282                     CSUM_PSEUDO_HDR;
3283                 copym->m_pkthdr.csum_data = 0xffff;
3284         }
3285         if_simloop(ifp, copym, AF_INET6, 0);
3286 }
3287
3288 /*
3289  * Chop IPv6 header off from the payload.
3290  */
3291 static int
3292 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
3293 {
3294         struct mbuf *mh;
3295         struct ip6_hdr *ip6;
3296
3297         ip6 = mtod(m, struct ip6_hdr *);
3298         if (m->m_len > sizeof(*ip6)) {
3299                 mh = m_gethdr(M_NOWAIT, MT_DATA);
3300                 if (mh == NULL) {
3301                         m_freem(m);
3302                         return ENOBUFS;
3303                 }
3304                 m_move_pkthdr(mh, m);
3305                 M_ALIGN(mh, sizeof(*ip6));
3306                 m->m_len -= sizeof(*ip6);
3307                 m->m_data += sizeof(*ip6);
3308                 mh->m_next = m;
3309                 m = mh;
3310                 m->m_len = sizeof(*ip6);
3311                 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
3312         }
3313         exthdrs->ip6e_ip6 = m;
3314         return 0;
3315 }
3316
3317 /*
3318  * Compute IPv6 extension header length.
3319  */
3320 int
3321 ip6_optlen(struct inpcb *inp)
3322 {
3323         int len;
3324
3325         if (!inp->in6p_outputopts)
3326                 return 0;
3327
3328         len = 0;
3329 #define elen(x) \
3330     (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
3331
3332         len += elen(inp->in6p_outputopts->ip6po_hbh);
3333         if (inp->in6p_outputopts->ip6po_rthdr)
3334                 /* dest1 is valid with rthdr only */
3335                 len += elen(inp->in6p_outputopts->ip6po_dest1);
3336         len += elen(inp->in6p_outputopts->ip6po_rthdr);
3337         len += elen(inp->in6p_outputopts->ip6po_dest2);
3338         return len;
3339 #undef elen
3340 }